Resin composition and display device using the same

ABSTRACT

The resin composition of the present invention is a resin composition characterized by including (a) a polyimide, a polybenzoxazole, a polyimide precursor or a polybenzoxazole precursor, (b) 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, or 2,3-dihydroxynaphthalene, and (c) a thermal cross-linking agent having a specific structure. By the use of the resin composition of the present invention, it is possible to reduce the transmittance in the visible region of a cured film while maintaining the transmittance of a resin film before curing.

CROSS REFERENCE

The present application is a 37 C.F.R. §1.53 (b) divisional of, andclaims priority to, U.S. application Ser. No. 13/146,794, filed Aug. 9,2011. application Ser. No. 13/146,794 is the national phase under 35U.S.C. §371 of International Application No. PCT/JP2010/050402, filed onJan. 15, 2010, which claims priority to Japanese Application No.2009-017790 filed on Jan. 29, 2009. The entire contents of each of theseapplications is hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to resin compositions. Particularly, itrelates to resin compositions suited for applications such as surfaceprotective films and interlayer dielectric films of semiconductorelements, dielectric layers of organic electroluminescent (hereinafterreferred to as EL) elements, planarization films of thin film transistor(hereinafter referred to as TFT) substrates for the driving of displaydevices using organic EL elements, wire-protecting dielectric films ofcircuit boards, on-chip microlens of solid imaging elements,planarization films for displays and solid imaging elements, and solderresists for circuit boards.

BACKGROUND ART

Cured films produced by curing compositions containing polyimide orpolybenzoxazole have been used widely for dielectric films, protectivefilms, planarization films, and the like of semiconductor elements ordisplay devices. Particularly in display devices, it is required toreduce the transmittance of a cured film in order to increase contrastin applications such as, for example, a dielectric layer of an organicEL display and a black matrix of a liquid crystal display. In order toprevent malfunction caused by penetration of light into a TFT fordriving of a display device, a leak electric current, and the like, itis required to reduce the transmittance of a dielectric layer of anorganic EL device or a planarization film to be provided on a TFTsubstrate of an organic EL display. Examples of a technology of reducingthe transmittance of a visible region greater than a wavelength of 400nm in a cured film include a method of adding a colorant, such as carbonblack, an organic or inorganic pigment, and a dyestuff, to a resincomposition like that seen in a black matrix material for liquid crystaldisplays, an RGB paste material, and the like. Since resin compositionscontaining such colorants have absorption in a exposure wavelengthregion of 400 to 450 nm, it is difficult to use them as positive typephotosensitive resin compositions which are sensitized by making lightreach to a film bottom and therefore the use as a negative typephotosensitive resin composition such that a film thereof is photocuredfrom its surface is common.

Examples of a technology of reducing the transmittance of a cured filmof a positive type photosensitive resin composition include a positivetype radiative resin composition comprising an alkali-soluble resin, aquinone diazide compound, and a coloring composition of a leuco dye, adeveloping agent, and so on (see, for example, patent document 1), aphotosensitive resin in which a heat-sensitive material that will becomeblack upon heating has been added beforehand (see, for example, patentdocument 2), and a positive type photosensitive resin compositioncomprising an alkali-soluble resin, a quinone diazide compound, athermally coloring compound that colors upon heating and exhibits anabsorbance maximum at 350 nm or more and 700 nm or less, and a compoundthat has no absorbance maximum at 350 nm or more and less than 500 nmand has an absorbance maximum at 500 nm or more and 750 nm or less (see,for example, patent document 3). These are technologies of reducing thetransmittance of a cured film while keeping the transmittance in theexposure wavelength region of the resin film before curing high by usinga coloring compound that colors due to energy, such as heat. Therefore,these can impart both positive photosensitivity and negativephotosensitivity to resin compositions with high versatility.

PRIOR ART DOCUMENTS Patent Documents

-   [Patent Document 1] JP 2008-122501 A-   [Patent Document 2] JP 10-170715 A-   [Patent Document 3] US Patent Application Publication No.    2004/197703 Specification

SUMMARY OF THE INVENTION Problems to be Solved by Invention

Coloring compounds are compounds that will have intramolecularstructural change themselves due to heat to develop absorption in aspecified wavelength region. Recently, not only coloring compounds butalso resin compositions capable of developing absorption in an exposurewavelength region by other means have been demanded in order to improveversatility. Then, an object of the present invention is to provide aresin composition that can reduce the transmittance in the visibleregion of a cured film by the use of a combination of specific compoundswhile maintaining the transmittance of the resin film before curing.

Means to Solve the Problems

That is, the present invention provides a resin composition comprising(a) a polyimide, a polybenzoxazole, a polyimide precursor, or apolybenzoxazole precursor, (b) 1,5-dihydroxynaphthalene,1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, or2,3-dihydroxynaphthalene, and (c) a thermal cross-linking agent having astructure represented by the following formula (1) or a thermalcross-linking agent having a group represented by the following formula(2):

[kagaku 1]

in formula (1), R represents a linking group having 2 to 4 valencies, R¹represents a monovalent organic group having 1 to 20 carbon atoms, Cl,Br, I, or F, R² and R³ each represent CH₂OR⁵ (R⁵ is a hydrogen atom or amonovalent hydrocarbon group having 1 to 6 carbon atoms), R⁴ representsa hydrogen atom, a methyl group or an ethyl group, s represents aninteger of 0 to 2 and u represents an integer of 2 to 4;

—N(CH₂OR⁶)_(t)(H)_(v)  (2)

wherein in formula (2), R⁶ represents a hydrogen atom or a monovalenthydrocarbon group having 1 to 6 carbon atoms, t is 1 or 2 and v is 0 or1, provided that t+v is 1 or 2.

Effect of the Invention

According to the present invention, it is possible to obtain a resincomposition that can reduce the transmittance in the visible region of acured film while maintaining the transmittance of the resin film beforecuring.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a sectional view of a TFT substrate in which a planarizationfilm and a dielectric layer have been formed.

FIG. 2 is a sectional view of a TFT substrate in which a dielectriclayer has been formed.

FIG. 3 is a transmission spectra of the resin composition of Example 2before and after curing.

FIG. 4 is a transmission spectra of the resin composition of ComparativeExample 3 before and after curing.

MODE FOR CARRYING OUT THE INVENTION

The resin composition of the present invention comprises (a) apolyimide, a polybenzoxazole, a polyimide precursor, or apolybenzoxazole precursor, (b) 1,5-dihydroxynaphthalene,1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, or2,3-dihydroxynaphthalene, and (c) a thermal cross-linking agent having astructure represented by the formula (1) provided above or a thermalcross-linking agent having a group represented by the formula (2)provided above. The combination of component (b) and component (c) withthe resin of component (a) makes it possible to make a cured film colorat 400 to 450 nm to reduce the transmittance in the visible rangegreatly. Lack of any one of the three compounds (a) to (c) will resultin difficulty in the intended coloring at 400 450 nm. The componentswill be described below.

The resin composition of the present invention includes (a) a polyimide,a polybenzoxazole, a polyimide precursor, or a polybenzoxazoleprecursor. It may include two or more of them and also may include acopolymer that has two or more of their repeating units.

Polyimide and polybenzoxazole are resins that have a cyclic structure ofan imide ring or an oxazole ring in their main chain. The number ofrepetitions of the repeating units is preferably 10 to 100000.

Polyimide can be obtained by reacting a tetracarboxylic acid or itscorresponding tetracarboxylic dianhydride or correspondingtetracarboxylic acid diester dichloride with a diamine or itscorresponding diisocyanate compound or corresponding trimethylsilylateddiamine and it has a tetracarboxylic acid residue and a diamine residue.For example, it can be obtained by dehydration-cyclizing a polyamideacid, which is one of the polyimide precursors produced by making atetracarboxylic dianhydride react with a diamine, by heating treatmentor chemical treatment. In the heating treatment, a solvent thatazeotropically boils with water, such as m-xylene, may be added. Theheating treatment may be done at a low temperature of equal to or lowerthan 100° C. with the addition of a weakly acidic carboxylic acidcompound. Examples of the cyclization catalyst to be used for thechemical treatment include dehydration condensation agents such ascarboxylic anhydrides and dicyclohexyl carbodiimide and bases such astriethylamine. A description of the polyimide precursor will be madelater.

Polybenzoxazole can be obtained by making a bisaminophenol compoundreact with a dicarboxylic acid, its corresponding dicarboxylic acidchloride or corresponding dicarboxylic acid active ester and it has adicarboxylic acid residue and a bisaminophenol residue. For example, itcan be obtained by dehydration-cyclizing a polyhydroxyamide, which isone of the polybenzoxazole precursors produced by making abisaminophenol compound react with a dicarboxylic acid react, by heatingtreatment or chemical treatment. In the heating treatment, a solventthat azeotropically boils with water, such as m-xylene, may be added.Moreover, the heating treatment may be done at a low temperature ofequal to or lower than 200° C. with the addition of an acidic compound.Examples of the cyclization catalyst to be used for the chemicaltreatment include phosphoric anhydride, bases, and carbodiimidecompounds. A description of the polybenzoxazol precursor will be madelater.

In the present invention, from the viewpoint of solubility in an aqueousalkali solution, the polyimide preferably has an acidic group or anacidic group derivative such as OR⁷, SO₃R⁷, CONR⁷R⁸, COOR⁷, andSO₂NR⁷R⁸, in a tetracarboxylic acid residue or a diamine residue, and itmore preferably has a hydroxyl group. In addition, the polybenzoxazolepreferably has an acidic group or an acidic group derivative, such asOR⁷, SO₃R⁷, CONR⁷R⁸, COOR⁷, and SO₂NR⁷R⁸, in a dicarboxylic acid residueor a bisaminophenol residue, and it more preferably has a hydroxylgroup. R⁷ and R⁸ each represent a hydrogen atom or a monovalent organicgroup having 1 to 20 carbon atoms. The acidic group refers to a casewhere all of R⁷ or R⁸ are hydrogen atoms, and the acidic groupderivative refers to a case where a monovalent organic group having 1 to20 carbon atoms is contained in R⁷ or R⁸.

In the present invention, examples of preferred structures of atetracarboxylic acid residue of a polyimide and a dicarboxylic acidresidue of a polybenzoxazole (these are hereinafter referred to as anacid residue) include structures provided below or structures resultingfrom replacing 1 to 4 hydrogen atoms of those structures by an alkylgroup having 1 to 20 carbon atoms, a fluoroalkyl group, an alkoxylgroup, an ester group, a nitro group, a cyano group, a fluorine atom, ora chlorine atom. Two or more of these may be used together.

[kagaku 2]

[kagaku 3]

It is noted that J represents a direct bond, —COO—, —CONH—, —CH₂—, and—C₂H₄—, —O—, —C₃H₆—, —SO₂—, —S—, —Si(CH₃)₂—, —O—Si(CH₃)₂—O—, —C₆H₄—,—C₆H₄—O—C₆H₄—, —C₆H₄—C₃H₆—C₆H₄—, or —C₆H₄—C₃F₆—C₆H₄—.

In the present invention, examples of preferred structures of a diamineresidue of a polyimide and a bisaminophenol residue of a polybenzoxazole(these are hereinafter referred to as an amine residue) includestructures provided below or structures resulting from replacing 1 to 4hydrogen atoms of those structures by an alkyl group having 1 to 20carbon atoms, a fluoroalkyl group, an alkoxyl group, an ester group, anitro group, a cyano group, a fluorine atom, or a chlorine atom. Two ormore of these may be used together.

[kagaku 4]

[kagaku 5]

It is noted that J represents a direct bond, —COO—, —CONH—, —CH₂—,—C₂H₄—, —O—, —C₃H₆—, —SO₂—, —S—, —Si (CH₃)₂—, —O—Si (CH₃)₂—O—, —C₆H₄—,—C₆H₄—O—C₆H₄—, —C₆H₄—C₃H₆—C₆H₄—, or —C₆H₄—C₃F₆—C₆H₄—. R⁷ represents ahydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.

Of the component (a) to be used for the present invention, the polyimideprecursor and the polybenzoxazole precursor are resins that have anamide bond in their main chain and are dehydration-cyclized by heatingtreatment or chemical treatment to become the aforementioned polyimideand polybenzoxazole. The number of repetitions of the repeating units ispreferably 10 to 100000. Examples of the polyimide precursor include apolyamide acid, a polyamide acid ester, a polyamide acid amide, and apolyisoimide, and a polyamide acid and a polyamide acid ester arepreferred. Examples of the polybenzoxazole precursor include apolyhydroxyamide, a polyaminoamide, polyamide, and a polyamide-imide,and a polyhydroxyamide is preferred. In the present invention, from theviewpoint of solubility in an aqueous alkali solution, the polyimideprecursor and the polybenzoxazole precursor preferably have an acidicgroup or an acidic group derivative such as OR⁷, SO₃R⁷, CONR⁷R⁸, COOR⁷,and SO₂NR⁷R⁸, in an acid residue or an amine residue, and they morepreferably have a hydroxyl group. R⁷ and R⁸ represent hydrogen atoms ormonovalent organic groups having 1 to 20 carbon atoms. The acidic grouprefers to a case where all of R⁷ or R⁸ are hydrogen atoms, and theacidic group derivative refers to a case where a monovalent organicgroup having 1 to 20 carbon atoms is contained in R⁷ or R⁸.

Regarding the acid component that constitutes the acid residue of thepolyimide precursor and the polybenzoxazole precursor, examples of adicarboxylic acid include terephthalic acid, isophthalic acid,diphenylether dicarboxylic acid, bis(carboxyphenyl)hexafluoropropane,biphenyldicarboxylic acid, benzophenone dicarboxylic acid, andtriphenyldicarboxylic acid. Example of a tricarboxylic acid includetrimellitic acid, trimesic acid, diphenyl ether tricarboxylic acid, andbiphenyl tricarboxylic acid. Examples of a tetracarboxylic acid includearomatic tetracarboxylic acids, such as pyromellitic acid,3,3′,4,4′-biphenyl tetracarboxylic acid, 2,3,3′,4′-biphenyltetracarboxylic acid, 2,2′,3,3′-biphenyl tetracarboxylic acid,3,3′,4,4′-benzophenonetetracarboxylic acid, 2,2′,3,3′-benzophenonetetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane,2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane,1,1-bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(2,3-dicarboxyphenyl)ethane,bis(3,4-dicarboxyphenyl)methane, bis(2,3-dicarboxyphenyl)methane,bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)ether,1,2,5,6-naphthalenetetracarboxylic acid,2,3,6,7-naphthalenetetracarboxylic acid, 2,3,5,6-pyridinetetracarboxylicacid and 3,4,9,10-perylene tetracarboxylic acid, and aliphatictetracarboxylic acids, such as butanetetracarboxylic acid, acyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylicacid, cyclohexanetetracarboxylic acid,bicyclo[2.2.1.]heptanetetracarboxylic acid,bicyclo[3.3.1.]tetracarboxylic acid, bicyclo[3.1.1.]hept-2-enetetracarboxylic acid, bicyclo[2.2.2.]octane tetracarboxylic acid, andadamantane tetracarboxylic acid. Two or more of these may be usedtogether. More preferred are the dicarboxylic acids, tricarboxylic acidsor tetracarboxylic acids provided above as examples whose 1 to 4hydrogen atoms have been substituted with an acidic group or acidicgroup derivative, such as OR⁷, SO₃R⁷, CONR⁷R⁸, COOR⁷, and SO₂NR⁷R⁸,preferably with a hydroxyl group, a sulfonic acid group, a sulfonic acidamide group, or a sulfonic acid ester group.

These acids each can be used as it is or in the form of an acidanhydride or an active ester.

By the use of a silicon atom-containing tetracarboxylic acid such asdimethylsilanediphthalic acid and 1,3-bis(phthalicacid)tetramethyldisiloxane, it is possible to enhance the adhesionproperty to a substrate and the resistance to oxygen plasma to be usedfor washing and resistance to a UV ozone treatment. These siliconatom-containing tetracarboxylic acids are preferably used in 1 to 30 mol% of the whole acid component.

Examples of the diamine component that constitutes the amine residue ofthe polyimide precursor and the polybenzoxazole precursor includehydroxyl group-containing diamines, such asbis(3-amino-4-hydroxyphenyl)hexafluoropropane,bis(3-amino-4-hydroxyphenyl)sulfone,bis(3-amino-4-hydroxyphenyl)propane,bis(3-amino-4-hydroxyphenyl)methylene,bis(3-amino-4-hydroxyphenyl)ether, bis(3-amino-4-hydroxy)biphenyl,bis(3-amino-4-hydroxyphenyl)fluorene, carboxyl group-containingdiamines, such as 3,5-diaminobenzoic acid and3-carboxy-4,4′-diaminodiphenyl ether, sulfonic acid-containing diamines,such as 3-sulfonic acid-4,4-diaminodiphenyl ether,dithiohydroxyphenylenediamine, 3,4′-diaminodiphenyl ether,4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenylmethane,4,4′-diaminodiphenylmethane, 3,4′-diaminodiphenyl sulfone,4,4′-diaminodiphenyl sulfone, 3,4′-diaminodiphenylsulfide,4,4′-diaminodiphenylsulfide, 1,4-bis(4-aminophenoxy)benzene, benzine,m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine,2,6-naphthalenediamine, bis(4-aminophenoxyphenyl)sulfone,bis(3-aminophenoxyphenyl)sulfone, bis(4-aminophenoxy)biphenyl,bis{4-(4-aminophenoxy)phenyl}ether, 1,4-bis(4-aminophenoxy)benzene,2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-diethyl-4,4′-diaminobiphenyl,3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-diethyl-4,4′-diaminobiphenyl,2,2′,3,3′-tetramethyl-4,4′-diaminobiphenyl,3,3′,4,4′-tetramethyl-4,4′-diaminobiphenyl,2,2′-di(trifluoromethyl)-4,4′-diaminobiphenyl, or compounds eachresulting from replacing some halogen atoms of the aromatic ring of eachof the foregoing by an alkyl group or a halogen atom, aliphaticdiamines, such as cyclohexyldiamine and methylenebiscyclohexylamine.Furthermore, these diamines may be substituted with an alkyl grouphaving 1 to 10 carbon atoms, such as a methyl group and an ethyl group,a fluoroalkyl group having 1 to 10 carbon atoms, such as atrifluoromethyl group, or a group such as F, Cl, Br, and I. Two or moreof these may be used together. For an application in which heatresistance is required, it is preferred to use an aromatic diamine in 50mol % or more of the whole diamine. In addition, the diamines providedabove as examples preferably have an acidic group or an acidic groupderivative, such as OR⁷, SO₃R⁷, CONR⁷R⁸, COOR⁷, and SO₂NR⁷R⁸, and theymore preferably have a hydroxyl group.

These diamines can be used as they are or in the form of a correspondingdiisocyanate compound or trimethylsilylated diamine.

The use of a silicon atom-containing diamine, such as1,3-bis(3-aminopropyl)tetramethyldisiloxane and1,3-bis(4-anilino)tetramethyldisiloxane, as a diamine component canenhance adhesion property to a substrate or resistance to oxygen plasmato be used for washing and resistance to a UV ozone treatment. Thesesilicon atom-containing diamines are preferably used in 1 to 30 mol % ofthe whole diamine component.

It is preferred to cap the end of a polyimide, a polybenzoxazole, apolyimide precursor, or a polybenzoxazole precursor with a monoaminehaving a hydroxyl group, a carboxyl group, a sulfonic acid group, or athiol group, an acid anhydride, an acid chloride, or a monocarboxylicacid. Two or more of these may be used together. The dissolution rate ofa resin to an aqueous alkali solution can be adjusted easily to apreferable range by the possession of the aforementioned group at aresin end.

Preferable examples of a monoamine include 5-amino-8-hydroxyquinoline,1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene,1-hydroxy-5-aminonaphthalene, 1-hydroxy-4-aminonaphthalene,2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene,2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene,1-carboxy-6-aminonaphthalene, 1-carboxy-5-aminonaphthalene,2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene,2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid,4-aminobenzoic acid, 4-aminosalicylic acid, 5-aminosalicylic acid,6-aminosalicylic acid, 2-aminobenzenesulfonic acid,3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid,3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol,4-aminophenol, 2-aminothiophenol, 3-aminothiophenol, and4-aminothiophenol.

Preferable examples of the acid anhydride, the monoacid chloride, themonocarboxylic acid, and the mono-active ester compound include acidanhydrides, such as phthalic anhydride, maleic anhydride, nasic acid,cyclohexane dicarboxylic acid anhydride, and 3-hydroxyphthalic acidanhydride; monocarboxylic acids, such as 3-carboxyphenol,4-carboxyphenol, 3-carboxythiophenol, 4-carboxythiophenol,1-hydroxy-7-carboxynaphthalene, 1-hydroxy-6-carboxynaphthalene,1-hydroxy-5-carboxynaphthalene, 1-mercapto-7-carboxynaphthalene,1-mercapto-6-carboxynaphthalene, 1-mercapto-5-carboxynaphthalene,3-carboxybenzenesulfonic acid, and 4-carboxybenzenesulfonic acid, andmonoacid chloride compounds resulting from conversion of their carboxylgroups to acid chlorides; monoacid chloride compounds resulting fromconversion of one carboxyl group of a dicarboxylic acid, such asterephthalic acid, phthalic acid, maleic acid, cyclohexanedicarboxylicacid, 1,5-dicarboxynaphthalene, 1,6-dicarboxynaphthalene,1,7-dicarboxynaphthalene, and 2,6-dicarboxynaphthalene, into an acidchloride; and mono-active ester compounds obtained through a reactionbetween a monoacid chloride compound and N-hydroxybenzotriazole orN-hydroxy-5-norbornene-2,3-dicarboxylmide.

The content of the end-capping agent, such as the aforementionedmonoamine, acid anhydride, acid chloride, and monocarboxylic acid, ispreferably within a range of 0.1 to 60 mol %, more preferably from 5 to50 mol %, of the number of moles of the charged acid component monomerto constitute an acid residue or the charged diamine component monomerto constitute an diamine residue. By adjusting the content to such arange, a resin composition that is moderate in viscosity of its solutionwhen applying the resin composition and that has superior filmproperties can be obtained.

The resin also may have a polymerizable functional group at its end.Examples of the polymerizable functional group include an ethylenicallyunsaturated linking group, anacetylene group, a methylol group, and analkoxymethyl group.

The end-capping agent having been introduced into a resin can bedetected easily by the following method. For example, an end-cappingagent can be detected easily by dissolving a resin into which theend-capping agent has been introduced in an acidic solution to decomposethe resin into an amine component and an acid component which areconstitutional units of the resin, and then measuring them by gaschromatography (GC) or NMR. Aside from this, a resin in which anend-capping agent has been introduced can be detected directly throughthe measurement of a pyrolysis gas chromatograph (PGC), an infraredspectrum, and ¹³C-NMR.

In the present invention, a polyimide precursor or a polybenzoxazoleprecursor is preferred as component (a) and a polyimide precursor ismore preferred. A polyimide precursor advances an imidation reaction inwhich an amide acid moiety is cyclized by curing calcination at about200° C., and a polybenzoxazole precursor advances an oxazolationreaction in which a hydroxyamide moiety is cyclized by curingcalcination at about 300° C., resulting in remarkable improvement inchemical resistance. The polyimide precursor makes it possible toobtaine chemical resistance at a lower calcination temperature. Aphotosensitive resin composition using such a precursor resin having aproperty to volumetrically shrink at the time of curing calcinationmakes it possible to obtain a pattern in a forward-tapered form byobtaining a fine pattern by an exposure-development step and thenperforming calcination. This pattern in a forward-tapered form issuperior in ability to cover an upper electrode when being used as adielectric film of an organic EL element, and it can prevent breakage ofwiring and can improve the reliability of an element.

The resin composition of the present invention may containalkali-soluble resins other than component (a). An alkali-soluble resinrefers to any resin having an acidic group to become soluble in alkaliand specific examples thereof include radically polymerizable polymershaving acrylic acid, a phenol novolak resin, and polyhydroxystyrene,polysiloxane. It is also permitted to adjust the alkali solubility byprotecting the acidic groups of these resins. Such a resin is asubstance that is soluble in an aqueous solution of an alkali, such ascholine, triethylamine, dimethylaminopyridine, monoethanolamine,diethylaminoethanol, sodium hydroxide, potassium hydroxide, and sodiumcarbonate as well as tetramethylammonium hydroxide. Although two or moresuch resins may be contained, their proportion to the whole resinincluding component (a) is preferably up to 50% by weight.

The resin composition of the present invention contains (b)1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene,1,7-dihydroxynaphthalene, or 2,3-dihydroxynaphthalene. Two or more ofthese may be contained. The possession of two hydroxyl groups results inbetter alkali developability in comparison to a case of possessing onehydroxyl group and can improve photosensitivity. The naphthalenestructure, which is a fused polycyclic structure, is higher in electrondensity than a monocyclic compound and it comes to have an increasedelectron density through its possession of two hydrogen groups and caneffectively cause an electrophilic addition reaction of a thermalcross-linking agent (c) described later. Moreover, the conjugation ofn-electrons is prone to spread in two or more directions to developcolor after the formation of a cross-linking reaction, and therefore, itis possible to greatly reduce the transmittance in the visible region ofa cured film by combining it with a thermal cross-linking agent (c)described later. Such an effect becomes particularly remarkable when thestructure has hydroxyl groups at 1,5-positions, 1,6-positions,1,7-positions, or 2,3-positions. Moreover, by a cross-linking reactionof the thermal cross-linking agent (c) and the above-mentioned component(a), it is possible to fix the compound of component (b) to component(a), which is superior in heat resistance, so that the chemicalresistance of a cured film can be improved.

The resin composition of the present invention may contain, in additionto (b) 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene,1,7-dihydroxynaphthalene, or 2,3-dihydroxynaphthalene, another fusedpolycyclic aromatic compound having two or more hydroxyl groups.

Examples of the skeleton structure of the fused polycyclic aromaticcompound having two or more hydroxyl groups include carbon fusedbicyclic structure, such as pentalene, indene, naphthalene, azulene,heptalene, and octalene, carbon fused tricyclic structure, such asas-indacene, s-indacene, biphenylene, acenaphthylene, fluorene,phenanthrene, and anthracene, carbon fused tetracyclic structure, suchas trindene, fluoranthene, acephenanthrylene, aceanthrylene,triphenylene, pyrene, chrysene, tetraphene, and naphthacene, and carbonfused pentacyclic structure, such as picene, perylene, pentaphene,pentacene, and tetraphenylene. A heterocyclic structure containingnitrogen, sulfur, or oxygen atoms instead of some carbon atoms of theaforementioned carbon fused polycyclic aromatic compounds is alsoavailable. Examples of the fused polycyclic aromatic heterocompoundinclude fused heterobicyclic compounds, such as benzofuran,benzothiophene, indole, benzimidazole, benzothiazole, purine, quinoline,isoquinoline, cinnoline, and quinoxaline, and fused heterotricycliccompounds, such as dibenzofuran, carbazole, acridine, and1,10-phenanthroline. Compounds each resulting from replacing somehydrogen atoms of a compound having a skeleton provided above as anexample by two or more hydroxyl groups are preferred as the fusedpolycyclic aromatic compound having two or more hydroxyl groups.

Specific examples of the fused polycyclic aromatic compound having twoor more hydroxyl groups include 1,4-dihydroxynaphthalene,2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene,1,8-dihydroxynaphthalene, 2,4-dihydroxyquinoline,2,6-dihydroxyquinoline, 2,3-dihydroxyquinoxaline,anthracene-1,2,10-triol, and anthracene-1,8,9-triol.

In the resin composition of the present invention, the content of (b)1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, or1,7-dihydroxynaphthalene is preferably 5 parts by weight or more, morepreferably 10 parts by weight or more relative to 100 parts by weight ofthe resin of component (a). It is preferably 120 parts by weight orless, and more preferably 100 parts by weight or less. If the content ofcomponent (b) is 5 parts by weight or more, the transmittance in thevisible region of a cured film can be reduced more. If it is 120 partsby weight or less, it is possible to maintain the strength of a curedfilm and reduce the percentage of water absorption. When containing twoor more kinds of component (a) or component (b), their total amount ispreferably within the above-mentioned range.

The resin composition of the present invention contains (c) a thermalcross-linking agent having a structure represented by the followingformula (1) or a thermal cross-linking agent having a group representedby the following formula (2). Two or more of these may be contained. Thethermal cross-linking agent of component (c) can reduce thetransmittance of the visible range greatly by cross-linking itself toboth (a) a polyimide, a polybenzoxazole, a polyimide precursor, or apolybenzoxazole precursor, and (b) 1,5-dihydroxynaphthalene,1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, or2,3-dihydroxynaphthalene, thereby linking the three components (a), (b),and (c) together. Moreover, it can increase the chemical resistance of acured film through a cross-linking reaction.

[kagaku 6]

In formula (1), R represents a linking group having 2 to 4 valencies. R¹represents a monovalent organic group having 1 to 20 carbon atoms, Cl,Br, I, or F. Monovalent hydrocarbon groups having 1 to 6 carbon atoms,such as a methyl group, an ethyl group, a propyl group, a butyl group, apentyl group, a hexyl group, a cyclopentyl group, and a cyclohexylgroup, are preferred as the monovalent organic group having 1 to 20carbon atoms. R² and R³ each represent CH₂OR⁵ (R⁵ is a hydrogen atom ora monovalent hydrocarbon group having 1 to 6 carbon atoms). R⁴represents a hydrogen atom, a methyl group or an ethyl group. srepresents an integer of 0 to 2 and u represents an integer of 2 to 4. Aplurality of R¹s is to R⁴s each may be the same or different. Examplesof the linking group R are provided below.

[kagaku 7]

In the above formula, R⁹ to R²⁷ each represent a hydrogen group, amonovalent organic group having 1 to 20 carbon atoms, Cl, Br, I, or F. Amethyl group, an ethyl group, a propyl group, a butyl group, a pentylgroup, a hexyl group, a cyclopentyl group, a cyclohexyl group, a benzylgroup, and a naphthyl group are preferred as the monovalent organicgroup having 1 to 20 carbon atoms.

—N(CH₂OR⁶)_(t)(H)_(v)  (2)

In the above formula (2), R⁶ represents a hydrogen atom or a monovalenthydrocarbon group having 1 to 6 carbon atoms. t represents 1 or 2 and vrepresents 0 or 1, provided that t+v is 1 or 2.

In the above formula (1), R² and R³ each represent a thermallycross-linkable group, CH₂OR⁵ (R⁵ is a hydrogen atom or a monovalenthydrocarbon group having 1 to 6 carbon atoms). R⁵ is preferably amonovalent hydrocarbon group having 1 to 4 carbon atoms because itleaves a moderate reactivity and excels in storage stability. In aphotosensitive resin composition containing a photo acid generator, aphotopolymerization initiator, or the like, R⁵ is more preferably amethyl group or an ethyl group.

In the thermal cross-linking agent represented by formula (1), thenumber of the functional groups of the thermally cross-linkable groupsaccounting for in one molecule is 4 to 8. If the number of thefunctional groups is less than 4, it is impossible to color the resincomposition after curing moderately and also impossible to reduce thetransmittance in the visible region of a cured film. On the other hand,if the number of the functional groups exceeds 8, it is difficult toobtain a compound that is high in purity and the stability of thecompound itself and the storage stability in a resin compositiondeteriorate.

The purity of the compound having a structure represented by formula (1)is preferably 75% or more, and more preferably 85% or more. If thepurity is 85% or more, the storage stability is good, a cross-linkingreaction of a resin composition is fully carried out, resulting in asuperior coloring property after curing, and it is possible to reducethe transmittance in the visible region of a cured film. Since it ispossible to reduce unreacted groups, that serve as water-absorptivegroups, it is possible to reduce the water absorptivity of a resincomposition. Examples of the method for obtaining a thermalcross-linking agent having a high purity include recrystallization anddistillation. The purity of the thermal cross-linking agent can bedetermined by liquid chromatography.

Preferable examples of the thermal cross-linking agent having astructure represented by formula (1) are given below.

[kagaku 8]

[kagaku 9]

In formula (2), R⁶, which is a hydrogen atom or a monovalent hydrocarbongroup having 1 to 6 carbon atoms, preferably is a monovalent hydrocarbongroup having 1 to 4 carbon atoms. From the viewpoint of the stability ofa compound or the storage stability in a resin composition, it ispreferred, in a photosensitive resin composition containing a photo acidgenerator, a photopolymerization initiator, or the like, that R⁶ be amethyl group or an ethyl group and it is preferred that the number ofthe (CH₂OR⁶) groups contained in the compound be 8 or less.

Preferable examples of the thermal cross-linking agent having a grouprepresented by formula (2) are given below.

[kagaku 10]

The content of (c) the thermal cross-linking agent having a structurerepresented by formula (1) or the thermal cross-linking agent having agroup represented by formula (2) is preferably 5 parts by weight or moreand more preferably is 10 parts by weight or more relative to 100 partsby weight of the resin of component (a). It is preferably 120 parts byweight or less, and more preferably 100 parts by weight or less. If thecontent of component (c) is 5 parts by weight or more, the transmittancein the visible region of a cured film can be reduced more. If it is 120parts by weight or less, the strength of a cured film is high and alsothe resin composition is superior in storage stability. When containingtwo or more kinds of component (a) or component (c), their total amountis preferably within the above-mentioned range.

The resin composition of the present invention may further comprise (d)a photo acid generator, or (e) a photopolymerization initiator and (f) acompound having two or more ethylenically unsaturated bonds and canimpart positive type or negative type photosensitivity.

Due to the inclusion of (d) the photo acid generator in the resincomposition of the present invention, an acid is generated by in a partexposed to light, so that the solubility of a part exposed to light inan aqueous alkali solution increases and a positive type relief patternin which the part exposed to light dissolves can be obtained. Moreover,the inclusion of (d) the photo acid generator and an epoxy compoundmakes it possible to obtain a negative type relief pattern in whichacids generated in a part exposed to light promotes the reaction of theepoxy compound, so that the part exposed to light becomes insoluble.

Examples of (d) the photo acid generator include quinone diazidecompounds, sulfonium salts, phosphonium salts, diazonium salts, andiodonium salts.

Examples of the quinone diazide compound include a compound in which thesulfonic acid of quinone diazide has been bonded to a polyhydroxycompound via an ester, a compound in which the sulfonic acid of quinonediazide has been sulfonamide-bonded to a polyamino compound, and acompound in which the sulfonic acid of quinone diazide has beenester-bonded and/or sulfonamide-bonded to a polyhydroxypolyaminocompound. It is preferred that 50 mol % or more of the whole functionalgroups of such a polyhydroxy compound or polyamino compound have beensubstituted with quinone diazide. It is preferred that two or more kindsof photo acid generators (d) be contained and a highly photosensitiveresin composition can be obtained.

In the present invention, a quinone diazide compound that has any of a5-naphthoquinone diazide sulfonyl group and a 4-naphthoquinone diazidesulfonyl group is preferably used. A 4-naphthoquinonediazide sulfonylester compound is suitable for i-line exposure because it has anabsorption in the i-line region of a mercury lamp. A5-naphthoquinonediazide sulfonyl ester compound is suitable for g-lineexposure because it has an absorption extending to the g-line region ofa mercury lamp. In the present invention, it is preferred to choose a4-naphthoquinonediazide sulfonyl ester compound and a5-naphthoquinonediazide sulfonyl ester compound depending upon thewavelength of light to be applied. A naphthoquinonediazide sulfonylester compound that has a 4-naphthoquinone diazide sulfonyl group and a5-naphthoquinone diazide sulfonyl group in the same molecule may becontained, and both a 4-naphthoquinonediazide sulfonyl ester compoundand a 5-naphthoquinonediazide sulfonyl ester compound may be contained.

Among photo acid generators (d), sulfonium salt, phosphonium salts,diazonium salts are preferred because they moderately stabilize the acidcomponent generated by exposure to light. Particularly, sulfonium saltsare preferred.

In the present invention, from the viewpoint of enhancement insensitivity, the content of the photo acid generator (d) is preferably0.01 to 50 parts by weight relative to 100 parts by weight of the resinof component (a). Among these, the range of 3 to 40 parts by weight ispreferred for a quinone diazide compound. The total amount of thesulfonium salt, the phosphonium salt, and the diazonium salt ispreferably within the range of 0.5 to 20 parts by weight. Furthermore, asensitizing agent or the like can also be contained according to need.When containing two or more kinds of component (d), their total amountis preferably within the above-mentioned range.

The photosensitive resin composition of the present invention mayfurther comprise (e) a photopolymerization initiator and (f) a compoundhaving two or more ethylenically unsaturated bonds. It is possible toobtain a negative type relief pattern in which active radicals generatedin the part exposed to light advance the radical polymerization ofethylenically unsaturated bonds, so that the part exposed to lightbecomes insoluble.

Examples of (e) the photopolymerization initiator includediethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one,4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone,1-hydroxycyclohexyl-phenyl ketone,1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime,2-methyl-[4-(methylthio)phenyl]-2-morpholinopropan-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, benzoin,benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether,benzoin isobutyl ether, benzophenone, methyl o-benzoylbenzoate,4-phenylbenzophenone, 4,4-dichlorobenzophenone, hydroxybenzophenone,4-benzoyl-4′-methyl-diphenyl sulfide, alkylated benzophenone,3,3′,4,4′-tetra(tert-butylperoxycarbonyl)benzophenone,4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benz enemethanaminium bromide, (4-benzoylbenzyl)trimethylammonium chloride,2-hydroxy-3-(4-benzoylphenoxy)-N,N,N-trimethyl-1-propene aminiumchloride monohydrate, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone,2,4-diethylthioxanthone, 2,4-dichlorothioxanthone,2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminiumchloride, 2,4,6-trimethylbenzoylphenylphosphine oxide,1,2-octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone,1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime),2,2′-bis (o-chlorophenyl)-4,5,4′,5′-tetraphenyl-1,2-biimidazole,10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzil,9,10-phenanthrenequinone, camphorquinone, methylphenylglyoxy ester,η5-cyclopentadienyl-eta6-cumenyl-iron(1+)-hexafluorophosphate(1−),diphenylsulfide derivatives,bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium4,4-bis(dimethylamino)benzophenone, 4,4-bis(diethylamino)benzophenone,thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone,4-benzoyl-4-methylphenyl ketone, dibenzyl ketone, fluorenone,2,3-diethoxyacetophenone, 2,2-dimethoxy-2-phenyl-2-phenylacetophenone,2-hydroxy-2-methylpropiophenone, p-t-butyldichloroacetophenone,benzilmethoxyethyl acetal, anthraquinone, 2-tert-butyl anthraquinone,2-aminoanthraquinone, β-chloroanthraquinone, anthrone, benzanthrone,dibenzsuberone, methyleneanthrone, 4-azidobenzalacetophenone,2,6-bis(p-azidobenzyliene)cyclohexane,2,6-bis(p-azidobenzyliene)-4-methylcyclohexanone,2-phenyl-1,2-butadione-2-(o-methoxycarbonyl)oxime,1,3-diphenylpropanetrione-2-(o-ethoxycarbonyl)oxime, naphthalenesulfonylchloride, quinolinesulfonyl chloride, N-phenylthioacridone,4,4-azobisisobutyronitrile, benzthiazole disulfide, triphenylphosphine,tetrabromocarbon, tribromophenylsulfone, benzoyl peroxide, andcombinations of photoreductive dyes, such as eosin and methylene blue,and reducing agent, such as ascorbic acid and triethanolamine. Two ormore of these may be contained.

In the present invention, the content of the photopolymerizationinitiator (e) is preferably 0.1 to 20 parts by weight relative to 100parts by weight of the resin of component (a). If it is 0.1 parts byweight or more, a sufficient amount of radical is generated byirradiation with light and photosensitivity increases. If it is 20 partsby weight or less, curing of a part unexposed to light caused by thegeneration of excessive radicals does not occur, resulting in increasein alkali developability. When containing two or more kinds of component(e), their total amount is preferably within the above-mentioned range.

Examples of the compound having two or more ethylenically unsaturatedbonds (f) include acrylic monomers such as ethylene glycoldimethacrylate, ethylene glycol diacrylate, diethylene glycoldimethacrylate, trimethylolpropane triacrylate, ethoxylated bisphenol Adimethacrylate, glycerin dimethacrylate, tripropylene glycoldimethacrylate, butanediol dimethacrylate, glycerin triacrylate,pentaerythritol triacrylate, pentaerythritol tetraacrylate,dipentaerythritol hexaacrylate, ethoxylated pentaerythritoltetraacrylate, and ethoxylated isocyanuric acid triacrylate. Two or moreof these may be contained.

In the present invention, the content of the compound having two or moreethylenically unsaturated bonds (f) is preferably 1 part by weight ormore, and more preferably 5 parts by weight of more relative to 100parts by weight of the resin of component (a). It is preferably 100parts by weight or less, and more preferably 50 parts by weight or less.When containing two or more kinds of component (f), their total amountis preferably within the above-mentioned range.

For the purpose of adjustment of solubility or the like, a compoundhaving only one ethylenically unsaturated bond may be contained in anamount of 1 to 50 parts by weight relative to 100 parts by weight of theresin of component (a). Examples of such a compound include acrylicacid, methacrylic acid, methyl acrylate, methyl methacrylate, butylacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate,dimethylacrylamide, dimethylaminoethyl methacrylate, acryloylmorpholin,1-hydroxyethyl alpha-chloroacrylate, 2-hydroxyethyl methacrylate,2-hydroxyethyl acrylate, 2-hydroxyethyl α-chloroacrylate,1-hydroxypropyl methacrylate, 1-hydroxypropyl acrylate, 1-hydroxypropylα-chloroacrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropylacrylate, 2-hydroxypropyl α-chloroacrylate, 3-hydroxypropylmethacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropylα-chloroacrylate, 1-hydroxy-1-methylethyl methacrylate,1-hydroxy-1-methylethyl acrylate, 1-hydroxy-1-methylethylα-chloroacrylate, 2-hydroxy-1-methylethyl methacrylate,2-hydroxy-1-methylethyl acrylate, 2-hydroxy-1-methylethylα-chloroacrylate, 1-hydroxybutyl methacrylate, 11-hydroxybutyl acrylate,1-hydroxybutyl α-chloroacrylate, 2-hydroxybutyl methacrylate,2-hydroxybutyl acrylate, 2-hydroxybutyl α-chloroacrylate, 3-hydroxybutylmethacrylate, 3-hydroxybutyl acrylate, 3-hydroxybutyl α-chloroacrylate,4-hydroxybutyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutylα-chloroacrylate, 1-hydroxy-1-methylpropyl methacrylate,1-hydroxy-1-methylpropyl acrylate, 1-hydroxy-1-methylpropylα-chloroacrylate, 2-hydroxy-1-methylpropyl methacrylate,2-hydroxy-1-methylpropyl acrylate, 2-hydroxy-1-methylpropylα-chloroacrylate, 1-hydroxy-2-methylpropyl methacrylate,1-hydroxy-2-methylpropyl acrylate, 1-hydroxy-2-methylpropylα-chloroacrylate, 2-hydroxy-2-methylpropyl methacrylate,2-hydroxy-2-methylpropyl acrylate, 2-hydroxy-2-methylpropylα-chloroacrylate, 2-hydroxy-1,1-dimethylethyl methacrylate,2-hydroxy-1,1-dimethylethyl acrylate, 2-hydroxy-1,1-dimethylethylα-chloroacrylate, 1,2-dihydroxypropyl methacrylate, 1,2-dihydroxypropylacrylate, 1,2-dihydroxypropyl α-chloroacrylate, 2,3-dihydroxypropylmethacrylate, 2,3-dihydroxypropyl acrylate, 2,3-dihydroxypropylα-chloroacrylate, 2,3-dihydroxybutyl methacrylate, 2,3-dihydroxybutylacrylate, 2,3-dihydroxybutyl α-chloro acrylate, p-hydroxystyrene,p-isopropenylphenol, phenethyl methacrylate, phenethyl acrylate,phenethyl α-chloroacrylate, N-methylolacrylamide,N-methylolmethacrylamide, α-chloroacrylic acid, crotonic acid,4-pentenoic acid, 5-hexenoic acid, 6-heptenoic acid, 7-octenoic acid,8-nonanoic acid, 9-decanoic acid, 10-undecylenic acid, brassidic acid,ricinoleic acid, 2-(methacryloxy)ethyl isocyanate, 2-(acryloyloxy)ethylisocyanate, and 2-(c-chloroacryloyloxy)ethyl isocyanate. Two or more ofthese may be contained.

The resin composition of the present invention may further contain (g) athermal acid generator. The thermal acid generator (g) generates an acidon heating after development described later, so that it promotes across-linking reaction of the resin of component (a) with the thermalcross-linking agent of component (c) and also promotes the cyclizationof the imide ring or the oxazole ring of the resin of component (a).This offers the improvement in chemical resistance of a cured film andsuccessfully reduces film loss. The acid to be generated from thethermal acid generator (g) is preferably a strong acid and, for example,aryl sulfone acids, such as p-toluenesulfonic acid and benzenesulfonicacid, and alkyl sulfonic acids, such as methanesulfonic acid,ethanesulfonic acid, and butanesulfonic acid, are preferred. In thepresent invention, the thermal acid generator preferably is an aliphaticsulfonic acid compound represented by formula (4) or (5) and it maycontain two or more kinds of such compounds.

[kagaku 11]

In the above formulae (4) and (5), R³⁰ to R³² each represent an alkylgroup having 1 to 10 carbon atoms or a monovalent aromatic group having7 to 12 carbon atoms. The alkyl group and the aromatic group may besubstituted and examples of a substituent include an alkyl group and acarbonyl group.

Specific examples of the compound represented by formula (4) include thefollowing compounds.

[kagaku 12]

Specific examples of the compound represented by formula (5) include thefollowing compounds.

[kagaku 13]

From the viewpoint of promoting a cross-linking reaction, the content ofthe thermal acid generator (g) is preferably 0.1 parts by weight ormore, more preferably 0.3 parts by weight or more, and even morepreferably 0.5 parts by weight or more relative to 100 parts by weightof the resin of component (a). On the other hand, from the viewpoint ofthe electrically insulating property of a cured film, it is preferably20 parts by weight or less, more preferably 15 parts by weight or less,and even more preferably 10 parts by weight or less. When containing twoor more kinds of component (g), their total amount is preferably withinthe above-mentioned range.

The resin composition of the present invention can contain (h) a filler.In the case of using the resin composition of the present invention as asolder resist for circuit boards, the inclusion of the filler (h) has aneffect of exhibiting thixotropy to maintain a pattern at a prescribedsize in the course of coating the composition by screen printing anddrying it. Moreover, an effect to control shrinkage caused by heatcuring is also expectable.

Among fillers (h), examples of insulative fillers include calciumcarbonate, silica, alumina, aluminum nitride, titanium oxide,andsilica-titaniumoxide composite particles, and silica, titanium oxide,and silica-titanium oxide composite particles are preferred. Examples ofthe electrically conductive filler include gold, silver, copper, nickel,aluminum, and carbon, and silver is preferred. Two or more of these maybe contained depending upon the intended application. The content of thefiller (h) is preferably within the range of 5 to 500 parts by weightrelative to 100 parts by weight of component (a). The number averageparticle diameter of the filler (h) is preferably 10 μm or less and morepreferably 2 μm or less. The use of two or more fillers differing innumber average particle diameter in combination is also preferred fromthe viewpoint of imparting thixotropy and stress relaxation.

The use of particles having a number average particle diameter of 100 nmor less, which are so-called nanoparticles, as the filler (h) makes itpossible to adjust physical properties such as index of refraction whilemaintaining light transmittance. Particularly, the use of nanoparticleswith a high index of refraction makes it possible to develop a hightransmittance and a high index of refraction simultaneously. The mixingof such nanoparticle makes it possible to be used suitably as alow-temperature-curable optical thin film, such as an on-chip microlensof a solid imaging element and a planarization film for displays andsolid imaging elements. Examples of particles suitable for theabove-mentioned purpose include tin oxide-aluminum oxide mixedparticles, zirconium oxide-aluminum oxide mixed particles, zirconiumoxide-silicon oxide mixed particles, tin oxide particles, zirconiumoxide-tin oxide mixed particles, titanium oxide particles, tinoxide-titanium oxide mixed particles, silicon oxide-titanium oxide mixedparticles, zirconium oxide-titanium oxide mixed particles, and zirconiumoxide particles. The surface of particles may be coated with anothersubstance. Although the above-mentioned particles may be either in theform of a powder or in the form of sol, they are preferably in the formof sol from the viewpoint of easiness with which they are dispersed. Inview of transmittance, the number average particle diameter of thenanoparticles is preferably 50 nm or less and more preferably 30 nm orless.

The number average particle diameter of a filler can be measured byusing various particle counters. The average particle diameter ofnanoparticles can be measured by, for example, a gas adsorption method,a dynamic light scattering method, an X-ray small angle scatteringmethod, or a method of measuring particle diameters directly with atransmission electron microscope. Although the particle diameterobtained by these measuring methods may be in volume average or in massaverage, it can be converted into a number average molecular weight withthe assumption that the shape of a particle is spherical.

The resin composition of the present invention can contain a thermallycoloring compound that colors on heating to exhibit an absorbancemaximum at 350 nm or longer and 700 nm or shorter or an organic pigmentor dyestuff that has no absorbance maximum at 350 nm or longer andshorter than 500 nm and has an absorbance maximum at 500 nm or longerand 750 nm or shorter. The coloring temperature of the thermallycoloring compound is preferably 120° C. or higher and more preferably is150° C. or higher. The heat resistance under high temperature conditionsbecomes better and the light resistance becomes better without theoccurrence of fading due to prolonged ultraviolet-visible lightirradiation as the coloring temperature of the thermally coloringcompound becomes higher.

Examples of the thermally coloring compound include heat-sensitive dyes,pressure-sensitive dyes, and hydroxyl group-containing compounds havinga triarylmethane skeleton.

The resin composition of the present invention may contain an adhesionpromoter. Examples of the adhesion promoter include silane couplingagents such as vinyltrimethoxysilane, vinyltriethoxysilane,epoxycyclohexylethyltrimethoxysilane, 3-glycidoxypropyltrimetoxysilane,3-glycidoxypropyltriethoxysilane, p-styryl trimethoxysilane,3-aminopropyl trimethoxysilane, 3-aminopropyltriethoxysilane, andN-phenyl-3-aminopropyltrimethoxysilane, titanium chelating agents,aluminum chelating agents, compounds to be obtained by reacting anaromatic amine compound with an alkoxy group-containing siliconcompound. Two or more of these may be contained. Inclusion of suchadhesive promoters can enhance the adhesion property with a basesubstrate, such as a silicon wafer, ITO, SiO₂, and silicon nitride,when, for example, developing a photosensitive resin film. Moreover, itis possible to enhance resistance to oxygen plasma and UV ozonetreatment to be used for washing or the like. The content of theadhesion promoter is preferably 0.1 to 10 parts by weight per 100 partsby weight of the resin of component (a).

The resin composition of the present invention may contain an adhesionpromoter. Examples of the adhesion promoter includealkoxysilane-containing aromatic amine compounds, aromatic amidecompounds, and non-aromatic silane compounds. Two or more of these maybe contained. Inclusion of such compounds can improve the adhesiveproperty with a substrate after curing. Specific examples of thealkoxysilane-containing aromatic amine compounds and aromatic amidecompounds are provided below. In addition, compounds obtainable byreacting an aromatic amine compound with an alkoxy group-containingsilicon compound can also be used and examples thereof include compoundsobtainable by reacting an aromatic amine compound with an alkoxysilanecompound has a group that reacts with an amino group, such as an epoxygroup and a chloromethyl group.

[kagaku 14]

Examples of the non-aromatic silane compounds include vinyl silanecompounds, such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilan, and vinyltris(β-methoxyethoxy)silane, and carbon-carbonunsaturated bond-containing silane compounds, such as3-methacryloxypropyltrimethoxysilane, 3-acryloxyprophyltrimethoxysilane,p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, and3-methacryloxypropylmethyldiethoxysilane. Among these,vinyltrimethoxysilane and vinyltriethoxysilane are preferred.

The total content of the alkoxysilane-containing aromatic aminecompound, the aromatic amide compound, or the non-aromatic silanecompound is preferably 0.01 to 15 parts by weight relative to 100 partsby weight of the resin of component (a).

The resin composition of the present invention may contain a surfactant,by which the wettability with a substrate can be improved.

Examples of the surfactant include fluorine-based surfactants, such asFluorad (commercial name, available from Sumitomo 3M Ltd.), MEGAFAC(commercial name, available from DIC Corporation), and Sulfron(commercial name, available from Asahi Glass Co., Ltd.), organicsiloxane surfactants, such as KP341 (commercial name, available fromShin-Etsu Chemical Co., Ltd.), DBE (commercial name, ChissoCorporation), POLYFLOW, GLANOL (commercial names, available fromKyoeisha Chemical Co., Ltd.), and BYK (available from BYK-Chemie), andacrylic polymer surfactants, such as POLYFLOW (commercial name,available from Kyoeisha Chemical Co., Ltd.).

The resin composition of the present invention preferably contains asolvent. Examples of the solvent include polar aprotic solvents, such asN-methyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide,N,N-dimethylacetamide, and dimethyl sulfoxide, ethers, such astetrahydrofuran, dioxane, propylene glycol monomethyl ether, andpropylene glycol monoethyl ether, ketones, such as acetone, methyl ethylketone, diisobutyl ketone, and diacetone alcohol, esters, such as ethylacetate, butyl acetate, isobutyl acetate, propyl acetate, propyleneglycol monomethyl ether acetate, and 3-methyl-3-methoxy butyl acetate,alcohols, such as ethyl lactate, methyl lactate, diacetone alcohol, and3-methyl-3-methoxybutanol, aromatic hydrocarbons, such as toluene andxylene. Two or more of these may be contained. The content of thesolvent is preferably 100 to 2000 parts by weight relative to 100 partsby weight of the resin of component (a).

It is preferred for the resin composition of the present invention thatthe transmittance of a resin film before curing be high and thetransmittance in the visible region of a cured film be low.Specifically, it is preferred that the change in transmittance at awavelength of 450 nm before and after curing in a 3.0 μm thick film be20% or more. Here, the transmittance at a wavelength of 450 nm is anindex of the transmittance in the visible region. More specifically, itis preferred that the transmittance change be 20% or more, which iscalculated by the following formula from the transmittance at awavelength of 450 nm of a 3.0 μm thick film (before curing) to beobtained by coating a resin composition to a substrate and thenheat-treating it at 120° C. for 2 minutes and the transmittance at awavelength of 450 nm of a 3.0 μm thick film (after curing) to beobtained by further heat-treating the film before curing, at 230° C. for30 minutes under nitrogen flow. The present invention makes it possibleto realize such a change in transmittance easily.

Change in transmittance (%)=transmittance before curing(%)−transmittance after curing (%)

In the case of using the resin composition of the present invention as aphotosensitive resin, it is preferred that the transmittance of a resinfilm before curing be high. Specifically, the transmittance at awavelength of 450 nm of a resin film before curing is preferable 70% ormore and more preferably 90% or more. It is preferred that thetransmittance in the visible region of a cured film be low.Specifically, the transmittance at a wavelength of 450 nm of a curedfilm is preferable 70% or less and more preferably 60% or less. In thecase of using the resin composition of the present invention for aplanarization film or a dielectric film of a display device, it ispossible to prevent malfunction caused by penetration of light to a TFTfor driving, a leak electric current, or the like by adjusting thetransmittance of a cured film to be low. For this reason, the change intransmittance at a wavelength of 450 nm before and after curing ispreferably 20% to 100% and more preferably 30% to 100%.

Next, the method for producing the resin composition of the presentinvention is described. For example, a resin composition can be obtainedby dissolving the aforementioned components (a) to (c) and, ifnecessary, components (d) to (h), a thermally coloring component, anadhesion promoter, an adhesion promoter, a surfactant, or the like in asolvent. Examples of the dissolving method include agitation andheating. In the case of heating, it is preferred to adjust the heatingtemperature as far as the performance of a resin composition is notimpaired and it is usually from room temperature to 80° C. The order ofdissolving components is not particularly limited and, for example,there is method of dissolving them one after another from a compoundlower in solubility. As for a component that is prone to generatebubbles during dissolution by agitation, such as surfactants and someadhesion promoters, imperfect dissolution of other components due to thegeneration of bubbles can be prevented by dissolving the othercomponents and lastly adding that component.

It is preferred to filter the resulting resin composition with a filterto remove dusts or particles. The hole diameter of the filter is, forexample, but is not limited to, 0.5 μm, 0.2 μm, 0.1 μm, and 0.05 μm.Examples of the material of the filter includepolypropylene (PP),polyethylene (PE), nylon (NY), and polytetrafluoroethylene (PTFE), andpolyethylene and nylon are preferred. When the resin compositioncontains (h) a filler or an organic pigment, it is preferred to use afilter having a pore diameter larger than the particle diameter of them.

Next, the method for producing a cured film using the resin compositionof the present invention is described. A resin composition film isobtained by coating the resin composition of the present invention by aspin coating method, a slit coating method, a dip coating method, aspray coating method, a printing method, or the like. In advance ofcoating, the substrate to which the resin composition is to be coatedmay be pretreated with the adhesion promoter mentioned above. Forexample, there is a method of treating a substrate surface by using asolution in which 0.5 to 20% by weight of an adhesion promoter has beendissolved in a solvent such as isopropanol, ethanol, methanol, water,tetrahydrofuran, propylene glycol monomethyl ether acetate, propyleneglycol monomethyl ether, ethyl lactate, and diethyl adipate. Examples ofthe method of treating the substrate surface include spin coating, slitdie coating, bar coating, dip coating, spray coating, and vaportreatment. According to need, it is permitted to advance a reactionbetween the substrate and the adhesion promoter by conducting dryingtreatment under reduced pressure and then conducting heat treatment of50° C. to 300° C.

A cured film can be obtained by thermally treating a resulting resincomposition film. For example, a method of performing heat treatment at230° C. for 60 minutes, a method of performing heat treatment at 120 to400° C. for 1 minute to 10 hours, a method of performing heat treatmentat a low temperature of from room temperature to about 100° C. withaddition of a curing catalyst or the like, and a method of performingcuring at a low temperature of from room temperature to about 100° C. bya supersonic wave or electromagnetic wave treatment are mentioned.

When the resin composition of the present invention hasphotosensitivity, a negative type or positive type relief pattern can beobtained by irradiating the above-mentioned resin composition filmpartially with active light, such as an ultraviolet ray, and performingdeveloping treatment with a developing solution.

A cured film obtained by curing the resin composition of the presentinvention is suitably used as a dielectric film or a protective film ofwires. For example, there are an application for a dielectric film or aprotective film of wires in a printed board in which wires are formedfrom copper, aluminum, or the like on a film or a substrate of apolyimide and ceramics, and an application for a protective film forpartly soldering wires. When the resin composition contains anelectrically conductive filler, it can also be used as a wire material.

Moreover, a cured film obtained by curing the resin composition of thepresent invention is suitably used as a planarization film or adielectric layer of a display device having a substrate with a TFTformed thereon, a planarization film, a dielectric layer, and a displayelement in this order. Examples of a display device of this constitutioninclude a liquid crystal display device and an organic EL displaydevice. An active matrix type display device has a TFT on a substrate ofglass or the like and wires located in a side portion of the TFT andconnected to the TFT and has a planarization film thereon so that it maycover the irregularities of the wires, and it is further provided with adisplay element on the planarization film. The display element and thewires are connected via a contact hole formed in the planarization film.FIG. 1 shows a sectional view of a TFT substrate in which aplanarization film and a dielectric layer have been formed. A bottomgate type or top gate type TFT 1 in matrix form has been provided on asubstrate 6 and a dielectric film 3 has been formed with the TFT 1covered therewith. A wire 2 connected to the TFT 1 has been providedunder the dielectric film 3. Furthermore, on the dielectric film 3 havebeen provided a contact hole that opens the wire 2 and a planarizationfilm 4 with the wire and the contact hole embedded. The planarizationfilm 4 has been provided with an opening so as to reach the contact hole7 of the wire 2. Moreover, an ITO (transparent electrode) 5 has beenformed on the planarization film 4 in connection with the wire 2 via thecontact hole 7. Here, the ITO 5 serves as an electrode of a displayelement (for example, organic EL element). In addition, a dielectriclayer 8 is formed so that the periphery of the ITO 5 may be covered.This organic EL element may be either a top emission type which emitslight from the side opposite to the substrate 6 or a bottom emissiontype which extracts light from the side of the substrate 6. In theabove-described manner, an active matrix type organic EL display devicein which the organic EL elements each have been connected to a TFT 1 fordriving them.

Moreover, a cured film obtained by curing the resin composition of thepresent invention is suitably used as a dielectric layer of a displaydevice having a substrate with a TFT formed thereon, a dielectric layer,and a display element in this order. Examples of a display device havingsuch a constitution include organic EL display devices. An active matrixtype display device has a TFT on a substrate of glass or the like, andwires located in a side part of the TFT and connected to the TFT. Thedisplay element and the wires are connected via a contact hole formed inthe dielectric film. FIG. 2 shows a sectional view of a TFT substrate inwhich a dielectric layer has been formed. A bottom gate type or top gatetype TFT 1 in matrix form has been provided on a substrate 6 and adielectric film 3 has been formed with the TFT 1 covered therewith. Awire 2 connected to the TFT 1 has been provided under the dielectricfilm 3. Moreover, a contact hole 7 has been formed on the dielectricfilm 3 so that it may open the wire 2. An ITO (transparent electrode) 5has been formed in connection with the wire 2 via the contact hole 7.Here, the ITO 5 serves as an electrode of a display element (forexample, organic EL element). A dielectric layer 8 is formed so that theperiphery of the ITO 5, the TFT, and the steps of the wires may becovered. This organic EL element may be either a top emission type whichemits light from the side opposite to the substrate 6 or a bottomemission type which extracts light from the side of the substrate 6. Inthe above-described manner, an active matrix type organic EL displaydevice in which the organic EL elements each have been connected to aTFT 1 for driving them.

For example, in the case of an organic EL display device using a TFTcomprising, for example, amorphous silicone, micro crystal silicon, oran oxide semiconductor typified by In—Ga—Zn—O, unfavorable phenomena,such as a leak electric current or a photoinduced electric current, maybe caused due to penetration of blue light with a relatively highenergy. Since a cured film obtainable from the resin composition of thepresent invention has a moderate absorption near 450 nm, the occurrenceof a leak electric current, a photoinduced electric current, or the likeis prevented and a stable driving/light emission characteristic isobtained by using for a dielectric layer, a planarization film, etc. insuch an organic electroluminescence display device.

Moreover, a cured film to be obtained by curing the resin composition ofthe present invention can be used suitably for such applications as asurf ace protective film of a semiconductor element, such as LSI, aninterlayer dielectric film, and an adhesive and an under fill agent forpacking a device into a package, a capping agent that prevents coppermigration, an on-chip microlens of a solid imaging element, and aplanarization film for displays and solid imaging elements.

EXAMPLES

The present invention will be described below with reference toexamples, but the invention is not limited by these examples.

The evaluations of the resin compositions in examples were carried outby the following methods.

(1) Evaluation of Transmittance

A resin composition (hereinafter referred to as a varnish) was spincoated onto a 5 cm square glass substrate and was subjected to heattreatment (prebaking) at 120° C. for 2 minutes, so that a prebaked filmhaving a thickness of 3.0 μm was produced. A varnish was spin coated sothat its film thickness after curing might become 3.0 μm, and then heattreatment was carried out for 30 minutes at 230° C. under nitrogen flow(oxygen concentration 20 ppm or less) using an Inert Gas Oven INH-21CDavailable from Koyo Thermo Systems Co., Ltd., so that a cured film wasproduced. The thicknesses of the prebaked film and the cured film weremeasured using a SURFCOM 1400D (available from Tokyo Seimitsu Co.,Ltd.). For each of the thus obtained prebaked film and cured film, atransmission spectrum at wavelengths of 300 nm to 700 nm was measuredusing a UV-VIS spectrophotometer Multi-Spec-1500 (available fromShimadzu Corporation) and a transmittance at a wavelength of 450 nm wasmeasured. From a transmittance before curing (=prebaked film) and thatafter curing (=cured film), a change in transmittance was calculatedusing the following formula.

Change in transmittance (%)=transmittance before curing(%)−transmittance after curing (%)

When the change in transmittance is equal to or more than 20%, ajudgment as being good can be provided and when it is equal to or morethan 30%, a judgment as being very good can be provided.

(2) Evaluation of Sensitivity

The varnishes prepared in Examples 4 to 11 and Comparative Examples 5 to6 were each rotation coated onto a 6-inch silicon wafer and thenheat-treated for 3 minutes on a hot plate (Mark-7), so that 4.0 μm thickprebaked films were produced. The prebaking temperature was adjusted to120° C. for Examples 4 to 9 and Comparative Examples 5 to 6 and 100° C.for Examples 10 to 11. The resulting prebaked films were exposed with anexposure of 0 to 500 mJ/cm² at a 25 mJ/cm² step using an i-line stepper(DSW-8000, available from GCA). The line & space patterns used for theexposure are 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 50 and 100 μm. InExamples 10 to 11, heating was carried out at 100° C. for 1 minute afterthe exposure. After the exposure for Examples 4-9 or after the exposureand the following heating for Examples 10 to 11, development wasperformed in a 2.38 wt % aqueous solution of tetramethylammonium (TMAH)(ELM-D, available from Mitsubishi Gas Chemical Co., Inc.) for 60seconds, followed by rinsing with pure water, so that developed filmswere obtained. In the case of a positive type varnish, an exposure atwhich the exposed part was dissolved and disappeared through thedevelopment was defined as a photosensitivity. In the case of a negativetype varnish, the thickness of a film after development was measured andan exposure at which 90% of the thickness of a prebaked film remainedwas defined as a photosensitivity. The thickness after prebaking andthat after development were measured using a Lambda Ace STM-602available from Dainippon Screen Mfg. Co., Ltd. at an index of refractionof 1.63.

(3) Evaluation of Chemical Resistance

(i) The varnishes prepared in Examples 1 to 3 and Comparative Examples 1to 4 were each spin coated out onto a 6 inch silicon wafer and thenheat-treated for 3 minutes on a hot plate, so that 4.0 μm thick prebakedfilms were produced. On the other hand, films after development wereproduced from the varnishes prepared in Examples 4 to 11 and ComparativeExamples 5 to 6 by the method described in the foregoing (2). Theresulting prebaked films and film after development were heat-treated at230° C. for 30 minutes under nitrogen flow (oxygen concentration 20 ppmor less) using an Inert Oven INH-21CD available Koyo Thermo Systems Co.,Ltd., so that cured films were produced.

The resulting cured films were immersed in a stripping liquid 106available from Tokyo Ohka Kogyo Co., Ltd. at 70° C. for 10 minutes. Thethickness of a cured films before the stripping liquid treatment and thethickness of a cured film after that treatment were measured using aLambda Ace STM-602 available from Dainippon Screen Mfg. Co., Ltd. at anindex of refraction of 1.64, and then the reduction in film thicknesswas calculated. The reduction in film thickness is preferably 0.25 μm orless, more preferably 0.15 μm or less, and even more preferably 0.10 μmor less.

(ii) Cured films were produced by the method described in the foregoing(i) using the varnishes prepared in Examples 4 to 11 and ComparativeExamples 5 to 6. The resulting cured films were immersed in a strippingliquid 106 available from Tokyo Ohka Kogyo Co., Ltd. at 70° C. for 10minutes. A cured film after the stripping liquid treatment was observedwith an optical microscope of 20 magnifications, so that the presence ofcoming off of a pattern was evaluated. The smallest pattern having nocoming off of a pattern was defined as being a remaining pattern. Sincethe finer a pattern becomes, the more likely it comes off, when aremaining pattern is equal to or less than 20 μm, a judgment as beinggood can be provided and when it is equal to or less than 5 μm, ajudgment as being very good can be provided.

Synthesis Example 1 Synthesis of a Hydroxyl Group-Containing DiamineCompound

18.3 g (0.05 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane(BAHF, available from Central Glass Co., Ltd.) was dissolved in 100 mLof acetone and 17.4 g (0.3 mol) of propylene oxide (available from TokyoChemical Industry Co., Ltd.), followed by cooling to −15° C. A solutionin which 20.4 g (0.11 mol) of 3-nitrobenzoyl chloride (available fromTokyo Chemical Industry Co. Ltd.) had been dissolved in 100 mL ofacetone was dropped here. After the completion of the dropping,agitation was done at −15° C. for 4 hours and then the temperature wasreturned to room temperature. The precipitated white solid was collectedby filtration and then was vacuum dried at 50° C.

30 g of the resulting white solid was placed in a 300 mL stainless steelautoclave and was dispersed in 250 mL of methyl cellosolve, followed bythe addition of 2 g of 5% palladium-carbon (available from Wako PureChemical Industries, Ltd.). Hydrogen was introduced here with a balloonand a reduction reaction was performed at room temperature. About 2hours later, the reaction was terminated on confirmation of the factthat the balloon no longer shrank. After the termination of thereaction, the palladium compound, the catalyst, was removed byfiltration, followed by concentration with a rotary evaporator,affording a hydroxyl group-containing diamine compound represented bythe following formula.

[kagaku 15]

Synthesis Example 2 Synthesis of a Quinone Diazide Compound

Under dry nitrogen flow, 21.22 g (0.05 mol) of TrisP-PA (commercialname, available from Honshu Chemical Industry Co., Ltd.) and 26.8 g (0.1mol) of 5-naphthoquinonediazidosulfonyl chloride (NAC-5, available fromToyo Gosei Co., Ltd.) were dissolved in 450 g of 1,4-dioxane and thetemperature was adjusted to room temperature. 12.65 g of triethylamine,which had been mixed with 50 g of 1,4-dioxane, was dropped here so thatthe temperature of the system might not become equal to or higher than35° C. After the dropping, agitation was done at 40° C. for 2 hours. Atriethylamine salt was filtered and the filtrate was poured into water.Then a precipitate formed was collected by filtration and washed with 1L of 1% aqueous hydrochloric acid. Then it was further washed with 2 Lof water twice. The precipitation was dried in a vacuum dryer, so that aquinone diazide compound represented by the following formula wasobtained.

[kagaku 16]

Synthesis Example 3 Synthesis of Alkoxymethyl Group-Containing Compound(A-1)

(1) 103.2 g (0.4 mol) of 1,1,1-tris (4-hydroxyphenyl)ethane (TrisP-HAP,available from Honshu Chemical Industry Co., Ltd.) was dissolved in asolution in which 80 g (2.0 mol) of sodium hydroxide had been dissolvedin 800 g of pure water. After the complete dissolution, 686 g of 36-38wt % formalin was dropped at 20 to 25° C. over 2 hours. Then agitationwas done at 20 to 25° C. for 17 hours. This was neutralized by adding 98g of sulfuric acid and 552 g of water and then was left at rest for 2days. A needlelike white crystal formed after being left at rest wascollected by filtration and then was washed with 100 mL of water. Thewhite crystal was vacuum dried at 50° C. for 48 hours. When the driedwhite crystal was analyzed by a high-performance liquid chromatographavailable from Shimadzu Corporation at 254 nm using ODS as a column,acetonitrile/water=70/30 as a developing solvent, it was found that thestarting material had disappeared completely and the purity was 92%.Moreover, when analysis was done by NMR (GX-270, available from JEOLLtd.) using DMSO-d6 as a deuterated solvent, it was found to behexamethyloled TrisP-HAP.

(2) Next, the compound thus obtained was dissolved in 300 mL of methanoland was agitated at room temperature for 24 hours after the addition of2 g of sulfuric acid. To this solution was added 15 g of an anionic ionexchange resin (Amberlyst IRA96SB, available from Rohm and Haas),followed by agitation for 1 hour. Then the ion exchange resin wasremoved by filtration. After that, 500 mL of ethyl lactate was added andmethanol was removed by a rotary evaporator, so that an ethyl lactatesolution was formed. This solution was left at rest at room temperaturefor 2 days, so that a white crystal generated. When the obtained whitecrystal was analyzed by high-performance liquid chromatography, it wasfound to be a hexamethoxymethyl compound of TrisP-HAP (alkoxymethylgroup-containing compound (A-1)) represented by the following formulahaving a purity of 99%.

[kagaku 17]

Synthesis Example 4 Synthesis of Alkoxymethyl Group-Containing Compound(A-2)

(1) A dry white crystal was obtained in the same manner as in SynthesisExample 3(1) except for using 169.6 g (0.4 mol) of4,4′-[1-[4-[1-(4-hydroxyphenyl-1)-1-methylethyl]phenyl]ethylidene]bisphenol(TrisP-PA, available from Honshu Chemical Industry Co., Ltd.) instead of103.2 g (0.4 mol) of 1,1,1-tris (4-hydroxyphenyl)ethane (TrisP-HAP,available from Honshu Chemical Industry Co., Ltd.). This was analyzed byhigh-performance liquid chromatography in the same manner as inSynthesis Example 3 (1) to be found that the starting materials haddisappeared completely and the purity was 88%. Moreover, it wassubjected to NMR analysis in the same manner as in Synthesis Example 3(1), thereby being found to be hexamethyloled TrisP-PA.

(2) Next, a white crystal was obtained in the same manner as inSynthesis Example 3(2) except for using hexamethyloled TrisP-PA obtainedby the described method instead of the hexamethyloled TrisP-HAP. Theobtained white crystal was analyzed by high-performance liquidchromatography to be a hexamethoxymethyl compound of TrisP-PA(alkoxymethyl group-containing compound (A-2)) represented by afollowing formula having a purity of 99%.

[kagaku 18]

Synthesis Example 5 Synthesis of Alkoxymethyl Group-Containing Compound(A-3)

(1) Hexamethyloled TrisP-HAP having a purity of 92% was obtained in thesame manner as in Synthesis Example 3(1).

(2) Next, a white crystal was obtained in the same manner as inSynthesis Example 3 (2) except for using 300 mL of ethanol instead of300 mL of methanol. The obtained white crystal was analyzed byhigh-performance liquid chromatography to be a ethoxymethyl compound ofTrisP-HAP (alkoxymethyl group-containing compound (A-3)) represented bya following formula having a purity of 98%.

[kagaku 19]

Synthesis Example 6 Synthesis of Adhesion Promoter (B-1)

36.6 g (0.1 mol) of BAHF (available from Central Glass Co., Ltd.) wasdissolved in 100 g of ethyl lactate (EL, available from MusashinoChemical Laboratory, Ltd.). Subsequently, 55.6 g (0.2 mol) of3-glycidoxypropyltriethoxysilane (KBE-403, available from Shin-EtsuChemical Co., Ltd.) was added to this solution and agitated at 50° C.for 6 hours, so that adhesion promoter (B-1) was obtained.

Other thermal cross-linking agents and acid generators used in theExamples and the Comparative Examples are as follows.

[kagaku 20]

Example 1

32.9 g (0.09 mol) of BAHF was dissolved in 500 g of N-methyl pyrrolidone(NMP) under dry nitrogen flow. Here was added 31.0 g (0.1 mol) of3,3′,4,4′-diphenyl ether tetracarboxylic dianhydride (ODPA, availablefrom Manac Incorporated) together with 50 g of NMP, followed byagitation at 30° C. for 2 hours. Then 2.18 g (0.02 mol) of 3-aminophenol(available from Tokyo Chemical Industry Co. Ltd.) was added andagitation was continued at 40° C. for 2 hours. In addition, 5 g ofpyridine (available from Tokyo Chemical Industry Co. Ltd.) was dilutedin toluene (30 g, available from Tokyo Chemical Industry Co. Ltd.) andwas added to the solution, and then a cooling tube was attached and areaction was carried out for 2 hours with the temperature of thesolution kept at 120° C. and further for 2 hours at 180° C. whileazeotropically removing water together with toluene out of the system.The temperature of this solution was dropped to room temperature and thesolution was poured into 3 L of water, so that a white powder wasobtained. This powder was collected by filtration and further was washedwith water three times. After the washing, the white powder was dried ina vacuum dryer of 50° C. for 72 hours, so that a polyimide was obtained.

To 10 g of the polyimide were added 4 g of 1,5-dihydroxynaphthalene(available from Tokyo Chemical Industry Co. Ltd.), 5 g of thealkoxymethyl group-containing compounds (A-1) obtained in SynthesisExample 3, and 40 g of gamma-butyrolactone (GBL, available fromMitsubishi Chemical Corporation), so that a varnish of a polyimide resincomposition was obtained. As to the transmittance at 450 nm of a filmobtained using this varnish measured before or after curing, thetransmittance before curing was 95% and that after curing was 61%. Thismeans that the change in transmittance was 34%. When the chemicalresistance of the cured film was evaluated, the reduction in filmthickness was 0.10 μm or less and therefore the chemical resistance wasvery good.

Comparative Example 1

A varnish of a polyimide resin composition was obtained in the samemanner as in Example 1 except for adding 5 g of2,6-dimethoxymethyl-t-butylphenol (available from Honshu ChemicalIndustry Co., Ltd.) instead of the alkoxymethyl group-containingcompound (A-1) obtained in Synthesis Example 3. As to the transmittanceat 450 nm of a film obtained using this varnish measured before or aftercuring, the transmittance before curing was 96% and that after curingwas 85%. This means that the change in transmittance was 11%. When thechemical resistance of the cured film was evaluated, the film dissolvedcompletely.

Comparative Example 2

Into a 500-ml flask were charged 5 g of 2,2′-azobis(isobutyronitrile)and 200 g of tetrahydrofuran (THF). Then 35 g of methyl methacrylate(MM), 30 g of tert-butyl methacrylates (t-BM), and 35 g of methacrylicacid (MA) were charged and agitated at room temperature for a while, andafter replacing the inside of the flask with nitrogen, agitation wasdone at room temperature for 40 hours. 300 g of propylene glycolmonomethyl ether was added here and was agitated. After the completionof the agitation, the solution was charged into 2 L of water and aprecipitate of a polymer solid was collected by filtration. Furthermore,washing with 2 L of water was done three times and the collected polymersolid was dried at 50° C. in a vacuum dryer for 72 hours, so that anacrylic resin was obtained.

To 10 g of the obtained acrylic resin were added 4 g of1,5-dihydroxynaphthalene (available from Tokyo Chemical Industry Co.Ltd.), 5 g of the alkoxymethyl group-containing compound (A-1) obtainedin Synthesis Example 3, and 40 g of propylene glycol monomethyl etheracetate (PMA, available from Kuraray Co., Ltd.), so that a varnish of anacrylic resin composition was obtained. As to the transmittance at 450nm of a film obtained using this varnish measured before or aftercuring, the transmittance before curing was 97% and that after curingwas 93%. This means that the change in transmittance was 4%. When thechemical resistance of the cured film was evaluated, the film dissolvedcompletely.

Example 2

57.4 g (0.095 mol) of the hydroxyl group-containing diamine obtained inSynthesis Example 1 and 1.24 g (0.005 mol) of1,3-bis(3-aminopropyl)tetramethyldisiloxane (SiDA) were dissolved in 200g of NMP under dry nitrogen flow. 31.0 g (0.1 mol) of ODPA was addedhere and agitated at 40° C. for 2 hours. Then a solution in which 7.14 g(0.06 mol) of demethyl foramide dimethyl acetal (available fromMitsubishi Rayon Co., Ltd., DFA) had been diluted with 5 g of NMP wasdropped over 10 minutes. After the dropping, agitation was continued at40° C. for 2 hours. After the completion of the agitation, the solutionwas charged into 2 L of water and a precipitate of a polymer solid wascollected by filtration. Furthermore, washing with 2 L of water was donethree times and the collected polymer solid was dried at 50° C. in avacuum dryer for 72 hours, so that a polyamide acid was obtained.

A varnish of a polyimide precursor composition was obtained by weighing10 g of the thus obtained polyamide acid and dissolving 2 g of1,6-dihydroxynaphthalene (available from Tokyo Chemical Industry Co.Ltd.) and 4 g of MW-30HM (available from Sanwa Chemical Co., Ltd.) in 20g of EL and 20 g of GBL. As to the transmittance at 450 nm of a filmobtained using this varnish measured before or after curing, thetransmittance before curing was 94% and that after curing was 40%. Thismeans that the change in transmittance was 54%. The transmission spectrabefore and after curing are shown in FIG. 3. The transmittance of 400 nmto 550 nm dropped due to curing and therefore it was shown that coloringoccurred clearly in the visible range. When the chemical resistance ofthe cured film was evaluated, the reduction in film thickness was 0.10μm or less and therefore the chemical resistance was very good.

Example 3

A varnish of a polyimide resin composition was prepared in the samemanner as in Example 2 except for adding 10 g of the polyimide powderobtained in Example 1 instead of the polyamide acid and it wasevaluated. It was found that as to the transmittance at 450 nm of a filmmeasured before or after curing, the transmittance before curing was 95%and that after curing was 45%. This means that the change intransmittance was 50%. When the chemical resistance of the cured filmwas evaluated, the reduction in film thickness was 0.1 μm or less andtherefore the chemical resistance was very good.

Comparative Example 3

A varnish of a novolac resin composition was prepared in the same manneras in Example 2 except for using 10 g of a novolac resin PSF2808(available from Gun Ei Chemical Industry Co., Ltd.) instead of thepolyamide acid and it was evaluated. It was found that as to thetransmittance at 450 nm of a film measured before or after curing, thetransmittance before curing was 97% and that after curing was 88%. Thismeans that the change in transmittance was 9%. The transmission spectrabefore and after curing are shown in FIG. 4. The transmittance hardlydropped in the region of 400 nm or more after curing and therefore itwas shown that coloring did not occurred in the visible range. When thechemical resistance of the cured film was evaluated, the film dissolvedcompletely.

Comparative Example 4

A varnish of a polyhydroxystyrene resin composition was prepared in thesame manner as in Example 2 except for using 10 g of apolyhydroxystyrene resin MARUKA LYNCUR S-2 (available from MaruzenPetrochemical Co., Ltd.) instead of the polyamide acid and it wasevaluated. It was found that as to the transmittance at 450 nm of a filmmeasured before or after curing, the transmittance before curing was 97%and that after curing was 91%. This means that the change intransmittance was 6%.

When the chemical resistance of the cured film was evaluated, the filmdissolved completely.

Example 4

A varnish of a positive type photosensitive polyimide resin compositionwas obtained by further dissolving 4 g of the quinone diazide compoundobtained in Synthesis Example 2 in the varnish of Example 1. Using theobtained varnish, the evaluation of the transmittance, the evaluation ofthe chemical resistance and the evaluation of the photosensitivity of afilm before and after curing were performed as mentioned above. Thetransmittance at 450 nm was 95% before curing and 60% after curing. Thismeans that the change in transmittance was 35%. The photosensitivity was150 mJ/cm². The reduction in film thickness was 0.10 μm or less. Apattern of 10 μm or more remained.

Example 5

A varnish of a positive type photosensitive polyimide precursorcomposition was obtained by weighing 10 g of the polyamide acid obtainedin Example 2 and dissolving 4 g of 1,7-dihydroxynaphthalene (availablefrom Tokyo Chemical Industry Co. Ltd.), 5 g of the alkoxymethylgroup-containing compound (A-2) obtained in Synthesis Example 4, and 4 gof the quinonediazide compound obtained in Synthesis Example 2 in 20 gof EL and 20 g of GBL. Using the obtained varnish, the evaluation of thetransmittance, the evaluation of the chemical resistance and theevaluation of the photosensitivity of a film before and after curingwere performed as mentioned above. The transmittance at 450 nm was 90%before curing and 59% after curing. This means that the change intransmittance was 31%. The photosensitivity was 150 mJ/cm². Thereduction in film thickness was 0.15 μm. A pattern of 10 μm or moreremained.

Comparative Example 5

A varnish of a positive type photosensitive polyimide precursorcomposition was prepared in the same manner as in Example 5 except forusing 1-naphthol instead of 1,7-dihydroxynaphthalene and it wasevaluated. The transmittance at 450 nm was 90% before curing and 77%after curing. This means that the change in transmittance was 13%. Thereduction in film thickness was 0.20 μm. The photosensitivity was 300mJ/cm². A pattern of 20 μm or more remained.

Comparative Example 6

A varnish of a positive type photosensitive polyimide precursorcomposition was prepared in the same manner as in Example 5 except forusing 2,7-dihydroxynaphthalene instead of 1,7-dihydroxynaphthalene andit was evaluated. The transmittance at 450 nm was 90% before curing and74% after curing. This means that the change in transmittance was 16%.The reduction in film thickness was 0.15 μm. The photosensitivity was150 mJ/cm². A pattern of 10 μm or more remained.

Example 6

A varnish of a positive type photosensitive polyimide precursorcomposition was prepared by further dissolving, in the varnish ofExample 5, 0.5 g of5-propylsulfonyloxyimino-5H-thiophene-2-methylphenyl-acetonitrile(commercial name PAG-103, available from Ciba Specialty ChemicalsCorporation) as a thermal acid generator. Using the obtained varnish,the evaluation of the transmittance, the evaluation of the chemicalresistance and the evaluation of the photosensitivity of a film beforeand after curing were performed as mentioned above. The transmittance at450 nm was 90% before curing and 59% after curing. This means that thedecrease in transmittance was 31%. The photosensitivity was 150 mJ/cm².The reduction in film thickness was 0.10 μm or less. A pattern of 10 μmor more remained.

Example 7

A varnish of a positive type photosensitive polyimide precursorcomposition was obtained by further dissolving, in the varnish ofExample 5, 0.5 g of the adhesion promoter (B-1) obtained in SynthesisExample 6. Using the obtained varnish, the evaluation of thetransmittance, the evaluation of the chemical resistance and theevaluation of the photosensitivity of a film before and after curingwere performed as mentioned above. The transmittance at 450 nm was 90%before curing and 59% after curing. This means that the change intransmittance was 31%. The photosensitivity was 150 mJ/cm². Thereduction in film thickness was 0.15 μm. A pattern of 3 μm or moreremained.

Example 8

A varnish of a positive type photosensitive polyimide precursorcomposition was obtained by weighing 10 g of the polyamide acid obtainedin Example 2 and dissolving 4 g of 2,3-dihydroxynaphthalene (availablefrom Tokyo Chemical Industry Co. Ltd.), 5 g of the alkoxymethylgroup-containing compound (A-2) obtained in Synthesis Example 4, and 4 gof the quinonediazide compound obtained in Synthesis Example 2 in 20 gof EL and 20 g of GBL. Using the obtained varnish, the evaluation of thetransmittance, the evaluation of the chemical resistance and theevaluation of the photosensitivity of a film before and after curingwere performed as mentioned above. The transmittance at 450 nm was 93%before curing and 63% after curing. This means that the change intransmittance was 30%. The reduction in film thickness was 0.15 μm. Thephotosensitivity was 200 mJ/cm². A pattern of 10 μm or more remained.

Example 9

18.3 g (0.05 mol) of BAHF was dissolved in 50 g of NMP and 26.4 g (0.3mol) of glycidyl methyl ether under dry nitrogen flow and thetemperature of the solution was cooled to −15° C. Here was dropped asolution in which 7.4 g (0.025 mol) of diphenyl ether dicarboxylic aciddichloride (available from Nihon Nohyaku Co., Ltd.) and 5.1 g (0.025mol) of isophthalic acid chloride (available from Tokyo ChemicalIndustry Co. Ltd.) had been dissolved in 25 g of GBL so that theinternal temperature might not exceed 0° C. After the completion of thedropping, agitation was continued at −15° C. for 6 hours. After thecompletion of the reaction, the solution was charged into 3 L of watercontaining 10% by weight of methanol and a white precipitate wascollected. This precipitate was collected by filtration, washed withwater three times, and then dried in a vacuum dryer of 50° C. for 72hours, so that a polyhydroxyamide was obtained.

A varnish of a positive type photosensitive polybenzoxazole precursorcomposition was obtained by dissolving 10 g of the obtainedpolyhydroxyamide, 4 g of 1,5-dihydroxynaphthalene, 2 g of the quinonediazide compound of Synthesis Example 2, 0.5 g of WPAG-314 (commercialname, available from Wako Pure Chemical Industries, Ltd.), and 5 g ofMX-270 in 10 g of EL and 30 g of GBL. Using the obtained varnish, theevaluation of the transmittance, the evaluation of the chemicalresistance and the evaluation of the photosensitivity of a film beforeand after curing were performed as mentioned above. The transmittance at450 nm was 92% before curing and 61% after curing. This means that thedecrease in transmittance was 31%. The reduction in film thickness was0.25 μm and the photosensitivity was 160 mJ/cm². A pattern of 20 μm ormore remained.

Example 10

A varnish of a negative type photosensitive polybenzoxazole precursorcomposition was obtained by dissolving 10 g of the polyhydroxyamideobtained in Example 9, 1.5 g of 1,7-dihydroxynaphthalene, 0.5 g ofWPAG-314 (commercial name, available from Wako Pure Chemical Industries,Ltd.), 0.5 g of5-propylsulfonyloxyimino-5H-thiophene-2-methylphenyl-acetonitrile(commercial name PAG-103, available from Ciba Specialty ChemicalsCorporation) as a thermal acid generator, and 2 g of MW-30HM in 40 g ofGBL. Using the obtained varnish, the evaluation of the transmittance,the evaluation of the chemical resistance and the evaluation of thephotosensitivity of a film before and after curing were performed asmentioned above. The transmittance at 450 nm was 95% before curing and57% after curing. This means that the change in transmittance was 38%.The reduction in film thickness was 0.25 μm and the photosensitivity was200 mJ/cm². A pattern of 20 μm or more remained.

Example 11

A varnish of a negative type photosensitive polyimide resin compositionwas obtained by adding 5 g of 1,7-dihydroxynaphthalene, 4 g of thealkoxymethyl group-containing compounds (A-3) obtained in SynthesisExample 5, 2 g of ethyleneoxide-modified bisphenol A dimethacrylate (NKester BPE-100, available from Shin-Nakamura Chemical Co., Ltd.), 0.5 gof trimethylolpropane triacrylate, 0.1 g of1,2-octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)](available fromCiba Specialty Chemicals Corporation), 20 g of EL, and 20 g of GBL to 10g of the polyimide obtained in Example 1. Using the obtained varnish,the evaluation of the transmittance, the evaluation of the chemicalresistance and the evaluation of the photosensitivity of a film beforeand after curing were performed as mentioned above. The transmittance at450 nm was 94% before curing and 66% after curing. This means that thechange in transmittance was 28%. The reduction in film thickness was 0.1μm and the photosensitivity was 200 mJ/cm². A pattern of 10 μm or moreremained.

The compositions and evaluation results of Examples 1 to 11 andComparative Examples 1 to 6 are shown in Tables 1 to 3.

TABLE 1 Resin composition component Compound having two or more Fusedpolycyclic Thermal ethylenically aromatic compound cross- Photo acidunsaturated having a hydroxyl linking agent generatorPhotopolymerization bonds Resin group (Added (Added initiator (Added(Added amount) (Added amount) amount) amount) (Added amount) amount)Others Solvent Example 1 Polyimide 1,5- A-1 — — — — GBL (10 g)Dihydroxynaphthalene (5 g) (40 g) (4 g) Example 2 Polyamide acid 1,6-MW-30HM — — — — EL/GBL (10 g) Dihydroxynaphthalene (4 g) (20 g/20 g) (2g) Example 3 Polyimide 1,6- MW-30HM — — — — EL/GBL (10 g)Dihydroxynaphthalene (4 g) (20 g/20 g) (2 g) Example 4 Polyimide 1,5-A-1 Synthesis — — — GBL (10 g) Dihydroxynaphthalene (5 g) Example 2 (40g) (4 g) (4 g) Example 5 Polyamide acid 1,7- A-2 Synthesis — — — EL/GBL(10 g) Dihydroxynaphthalene (5 g) Example 2 (20 g/20 g) (4 g) (4 g)Example 6 Polyamide acid 1,7- A-2 Synthesis — — PAG-103 EL/GBL (10 g)Dihydroxynaphthalene (5 g) Example 2 (0.5 g) (20 g/20 g) (4 g) (4 g)Example 7 Polyamide acid 1,7- A-2 Synthesis — — Adhesion EL/GBL (10 g)Dihydroxynaphthalene (5 g) Example 2 promoter B-1 (20 g/20 g) (4 g) (4g) (0.5 g) Example 8 Polyamide acid 2,3- A-2 Synthesis — — — EL/GBL (10g) Dihydroxynaphthalene (5 g) Example 2 (20 g/20 g) (4 g) (4 g) Example9 Polyhydroxyamide 1,5- MX-270 Synthesis — — — EL/GBL (10 g)Dihydroxynaphthalene (5 g) Example 2 (10 g/30 g) (4 g) (2 g) WPAG- 314(0.5 g)

TABLE 2 Resin composition component Fused polycyclic aromatic compoundhaving a hydroxyl Thermal cross- Photo acid Resin group linking agentgenerator (Added amount) (Added amount) (Added amount) (Added amount)Example 10 Polyhydroxyamide 1,7- MW-30HM WPAG-314 (10 g)Dihydroxynaphthalene (2 g) (0.5 g) (1.5 g) Example 11 Polyimide 1,7- A-3— (10 g) Dihydroxynaphthalene (4 g) (5 g) Comparative Polyimide 1,5-2,6- — Example 1 (10 g) Dihydroxynaphalene Dimethoxymethyl- (4 g)t-butylphenol(5 g) Comparative Acrylic resin 1,5- A-1 — Example 2 (10 g)Dihydroxynaphthalene (5 g) (4 g) Comparative Novolak resin 1,6 MW-30HM —Example 3 (10 g) Dihydroxynaphthalene (4 g) (2 g) ComparativePolyhydroxystyrene 1,6- MW-30HM — Example 4 (10 g) Dihydroxynaphthalene(4 g) (2 g) Comparative Polyamide acid 1-Naphthol A-2 Synthesis Example2 Example 5 (10 g) (4 g) (5 g) (4 g) Comparative Polyamide acid 2,7- A-2Synthesis Example 2 Example 6 (10 g) Dihydroxynaphthalene (5 g) (4 g) (5g) Resin composition component Compound having two Photopolymerizationor more ethylenically initiator unsaturated (Added amount) bonds(Addedamount) Others Solvent Example 10 — — PAG-103 GBL (0.5 g) (40 g) Example11 1,2-Octanedione-1[4- Ethoxylated bisphenol — EL/GBL(phenylthio)phenyl]-2- A dimethacrylate (2 g) (20 g/20 g)(o-benzoyloxime) (0.1 g) Trimethylolpropane triacrylate (0.5 g)Comparative — — GBL Example 1 (40 g) Comparative — — PMA Example 2 (40g) Comparative — — EL/GBL Example 3 (20 g/20 g) Comparative — — EL/GBLExample 4 (20 g/20 g) Comparative — — EL/GBL Example 5 (20 g/20 g)Comparative — — EL/GBL Example 6 (20 g/20 g)

TABLE 3 Transmittance Transmittance at Transmittance at Change inChemical resistance 450 nm before 450 nm after transmittance atRemaining curing curing 450 nm Photosensitivity Loss of film patternExample 1 95% 61% 34% — ≦0.10 μm   — Example 2 94% 40% 54% — ≦0.10 μm  — Example 3 95% 45% 50% — ≦0.10 μm   — Example 4 95% 60% 35% 150 mJ/cm2≦0.10 μm   10 μm Example 5 90% 59% 31% 150 mJ/cm2 0.15 μm 10 μm Example6 90% 59% 31% 150 mJ/cm2 ≦0.10 μm   10 μm Example 7 90% 59% 31% 150mJ/cm2 0.15 μm  3 μm Example 8 93% 63% 30% 200 mJ/cm2 0.15 μm 10 μmExample 9 92% 61% 31% 160 mJ/cm2 0.25 μm 20 μm Example 10 95% 57% 38%200 mJ/cm2 0.25 μm 20 μm Example 11 94% 66% 28% 200 mJ/cm2 0.10 μm 10 μmComparative 96% 85% 11% — Completely — Example 1 dissolved Comparative97% 93% 4% — Completely — Example 2 dissolved Comparative 97% 88% 9% —Completely — Example 3 dissolved Comparative 97% 91% 6% — Completely —Example 4 dissolved Comparative 90% 77% 13% 300 mJ/cm2 0.20 μm 20 μmExample 5 Comparative 90% 74% 16% 150 mJ/cm2 0.15 μm 10 μm Example 6

Example 12

A bottom gate type TFT was formed on a glass substrate and wiring (1.0μm in height) connected to the TFT was formed. A dielectric film made ofSi₃N₄ was formed so that the TFT and the wires might be coveredtherewith. Next, a contact hole was formed in this dielectric film.

Moreover, a planarization film was formed on the dielectric film inorder to planarize the irregularities of the TFT and the wires. Theformation of the planarization film on the dielectric film was carriedout by spin coating the varnish of the photosensitive polyimideprecursor composition obtained in Example 5 onto the substrate,prebaking it on a hot plate at 120° C. for 3 minutes, then exposing anddeveloping it, and then subjecting it to heat calcination at 250° C. for60 minutes under air flow. The coating property at the time of coatingthe varnish was good and no development of wrinkles or cracks was foundin the cured film obtained after the exposure, development andcalcination. The average step height of the wires was 500 nm and thethickness of the produced planarization film was 2000 nm.

Next, a top emission type organic EL element was formed on the resultingplanarization film. First, a bottom electrode of ITO was formed on theplanarization film by sputtering in connection with a wire via a contacthole. Then, a resist was coated, prebaked, and exposed through a mask ofa desired pattern, thereby being developed. Pattern processing wascarried out by wet etching using an ITO etchant and using the resistpattern as a mask. Then, the resist pattern was stripped using a resiststripping liquid (a mixed liquid of monoethanolamine and DMSO). The thusobtained bottom electrode corresponds to an anode of an organic ELelement.

Next, a dielectric layer shaped so that it might cover the bottomelectrode was formed. For the dielectric layer was used similarly thevarnish of the photosensitive polyimide precursor composition obtainedin Example 5. By providing this dielectric layer it is possible toprevent short-circuit between the bottom electrode and an upperelectrode to be formed in a subsequent step. The dielectric layer waspatterned and was subjected to heating treatment at 250° C. for 60minutes, so that a dielectric layer having a moderate absorption near awavelength of 450 nm was formed.

Moreover, a hole transporting layer, red, green, and blue organiclight-emitting layers, and an electron transporting layer were providedone after another by vapor deposition via a desired pattern mask in avacuum deposition apparatus. Subsequently, an upper electrode ofaluminum was formed over the whole top surface of the substrate. Thiscorresponds to a cathode of an organic EL element. The aforementionedsubstrate obtained was taken out of the vacuum deposition apparatus andthen was sealed by bonding it to a sealing glass substrate using anultraviolet-curable epoxy resin.

In the above-described manner, an active-matrix type organic EL displaydevice in which a TFT has been connected to each organic EL element fordriving it was obtained. Good luminescence was exhibited when voltagewas applied via a driving circuit.

Example 13

A bottom gate type TFT was formed on a glass substrate and wiring (1.0μm in height) connected to the TFT was formed. A dielectric film made ofSi₃N₄ was formed so that the TFT and the wires might be coveredtherewith. Next, a contact hole was formed in this dielectric film. Thiswiring is an item for connecting a TFT and another TFT or an organic ELelement to be formed in a subsequent step and a TFT.

Next, a bottom electrode of ITO was formed by sputtering in connectionwith a wire via a contact hole. Then, a resist was coated, prebaked, andexposed through a mask of a desired pattern, thereby being developed.Pattern processing was carried out by wet etching using an ITO etchantand using the resist pattern as a mask. Then, the resist pattern wasstripped using a resist stripping liquid (a mixed liquid ofmonoethanolamine and DMSO). The thus obtained bottom electrodecorresponds to an anode of an organic EL element.

Next, a dielectric layer having such a shape that it could cover theperiphery of the bottom electrode, the TFT, and the steps of the wireswas formed. As to the dielectric layer, the varnish of thephotosensitive polyimide precursor composition obtained in Example 5 wasspin coated onto the substrate, subsequently dried under reducedpressure, then prebaked on a hot plate at 120° C. for 3 minutes, thenexposed and developed, and then subjected to heat calcination at 250° C.for 60 minutes under nitrogen flow. The coating property at the time ofspin coating the varnish was good and no development of wrinkles orcracks was found in the cured film obtained after the exposure,development and calcination. The average step height of the wires was500 nm and the thickness of the produced dielectric layer was 2000 nm.By providing this dielectric layer it is possible to preventshort-circuit between the bottom electrode and an upper electrode to beformed in a subsequent step. Thus, an dielectric layer having a moderateabsorption near a wavelength of 450 nm was formed.

Moreover, a hole transporting layer, red, green, and blue organiclight-emitting layers, and an electron transporting layer were providedone after another by vapor deposition via a desired pattern mask in avacuum deposition apparatus. Subsequently, an upper electrode ofaluminum was formed over the whole top surface of the substrate. Thiscorresponds to a cathode of an organic EL element. The aforementionedsubstrate obtained was taken out of the vacuum deposition apparatus andthen was sealed by bonding it to a sealing glass substrate using anultraviolet-curable epoxy resin.

In the above-described manner, an active-matrix type organic EL displaydevice in which a TFT has been connected to each organic EL element fordriving it was obtained. Good luminescence was exhibited when voltagewas applied via a driving circuit.

INDUSTRIAL APPLICABILITY

The resin composition of the present invention can be used suitably forapplications such as a surface protective film and an interlayerdielectric film of a semiconductor element, a dielectric layer of anorganic EL element, a planarization film of a TFT substrate for drivingof a display device using an organic EL element, a wire-protectingdielectric film of a circuit board, an on-chip microlens of a solidimaging element, a planarization film for displays and solid imagingelements, a solder resist for circuit boards, an underfill agent, and acapping agent for preventing copper migration.

EXPLANATION OF REFERENCE NUMERALS

-   1: TFT-   2: Wire-   3: Dielectric film-   4: Planarization film-   5: ITO-   6: Substrate-   7: Contact hole-   8: Dielectric layer

1. A resin composition comprising (a) a polyimide, a polybenzoxazole, ora resin that has an amide bond in its main chain and can form saidpolyimide or polybensoxazole by dehydration-cyclization effected by heattreatment or by chemical treatment, (b) 1,5-dihydroxynaphthalene,1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, or2,3-dihydroxynaphthalene, and (c) a thermal cross-linking agent having astructure represented by the following formula (1) or a thermalcross-linking agent having a group represented by the following formula(2):

wherein in formula (1), R represents a linking group having 2 to 4valencies, R¹ represents a monovalent organic group having 1 to 20carbon atoms, Cl, Br, I, or F, R² and R³ each represent CH₂OR⁵ (R⁵ is ahydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbonatoms), R⁴ represents a hydrogen atom, a methyl group or an ethyl group,s represents an integer of 0 to 2 and u represents an integer of 2 to 4;—N(CH₂OR⁶)_(t)(H)_(v)  (2) wherein in formula (2), R⁶ represents ahydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbonatoms, t is 1 or 2 and v is 0 or 1, provided that t+v is 1 or
 2. 2. Theresin composition according to claim 1, wherein the change intransmission of light having a wavelength of 450 nm for a prebaked filmand a cured film each having a thickness of 3.0 μm of said resincomposition is 20% or more.
 3. A display device comprising a substratein which a thin film transistor has been formed, a planarization filmand/or a dielectric layer and a display element in this order, whereinsaid planarization film and dielectric layer are obtained by curing theresin composition according to claim
 1. 4. The display device accordingto claim 3, wherein the display element is an organic electroluminescentelement.